Deep in the Heart of France: A Guide to the Loire Valley's Contemporary Caves

By Robert Bonnell

It is not common knowledge, even elsewhere in France, that the Loire Valley, that natural dividing line between the north and the south of France, is riddled with caves. Almost all of them are human creations, cavities hollowed out of the earth in the course of the last two millennia or more. Originally some caves were excavated to serve as refuges from marauders, others as stone quarries, others as mines. Once created, a variety of uses could be found for a cave, not least of which was as habitation.

In earlier times, a broad cross-section of social classes lived in cave habitations, but by the 19th century living in this sort of digs had been relegated to the poor. By the mid-20th century only a handful of cave dwellers hung on underground, and to live in a cave was considered something of a disgrace.

There were other uses for the caves, though, once the extraction of the stone had ceased. Wineries quickly come to mind. Caves were used to make and age still wines, of course, but the sparkling wine industry, established in the Loire Valley in the early 19th century, put large sections of abandoned caves to use for the aging of its product. Mushroom cultivation, also brought to the Loire Valley in the 19th century, was a major industry in the region until fairly recently. A once-thriving silk industry often used caves to raise silkworms.

At the beginning of the 21st century the wineries are still going strong, but most of the other cave-based industries have either died out or have been reduced considerably. Loire Valley caves are now much more likely to be reborn as tourist sites (restaurants, lodgings, museums) or once again, habitation. New technologies and a newfound respect for caves' ecological qualities have led to a renaissance of cave living. The troglodyte lifestyle appears to have a bright future.

• Language: English
• Publisher: Robert Bonnell
• Release date: Apr 4, 2012
• ISBN: 9782746647008

Robert Bonnell

Robert Bonnell, originally from California, has lived in a semi-troglo house in the Loire Valley since 2002. He has dragged his lovely wife Annette into more caves than she would like to remember.

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Deep in the Heart of France

A Guide to the Loire Valley’s Contemporary Caves

Robert Bonnell

Copyright 2012 Robert Bonnell

Cover photo copyright 2012 Joseph Vitone

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For Annette

Table of Contents

Author’s Preface

Introduction - Caves in France?

Visiting the Troglodyte World

Geology, Quarrying and Later Uses

Sleeping and Eating in Caves

Practical Matters

About The Site Reviews

Chapter 1: Western Anjou (Maine-et-Loire) and Mayenne

Limestone Caverns, North of the Loire

A Granite Museum and Quarries

A Slate Mine in Black Anjou

A Hard Rock Museum and a Walk Through the Slag Heaps

The Apocalypse in a Château

Caves Under Restoration

Chapter 2: Anjou (Maine-et-Loire) – West of Saumur

Cave Gallery of the Artist Richard Rak

A Troglo Gîte Near Coutures

Counter-Culture Caves

Top-Rate Fouées in Grézillé

A Fouée Restaurant, a Gîte and Hot Air Balloons

Sleep in a Dorm, Cook in a Cave, Save Lots of Money

Descending Into the Sculpture

The Pottery Cave of Gennes

Sleep in a Mariner’s Cave

Of Mushrooms and Snails

Chapter 3: Anjou (Maine-et-Loire) – South and Southwest of Saumur

The Cave of Sculptures

An Extensive Underground Village

Two Great Cave Restaurants in Rochemenier

Sleeping in Rochemenier

An Old-Fashioned Troglodyte and His Village

Down in a Cathedral

Sarcophagi and More

Pottery Workshop The Blue Rose

A Sand Quarry, with Essence of Rose and Violet

A Farm of Yesteryear With Caves

A Magnificent Zoo in a Quarry

Staying in Your Own Private World

Cathedral Cave Dining in Central Doué-la-Fontaine

Cathedral Cave Dining on the Outskirts of Doué-la-Fontaine

The Living Mushroom Cave

A Gîte in Great-Grandma’s Cave

Cave Lodgings South of Le Puy-Notre-Dame

A Silkworm Cave in Anjou

Chapter 4: Anjou (Maine-et-Loire) – Saumur and Vicinity

Carved Mini-Monuments of the Loire

A Mushroom Museum Par Excellence

Four Sparkling Wine Caves All in a Row

And Still More Saumur Bubbles

A Fouée Restaurant in Saumur

A Fouée Restaurant and Disco in Saumur

A Semi-Troglo B&B in Saumur

Where Cave Cuisine Began

Chapter 5: Anjou (Maine-et-Loire) – East of Saumur

A Gîte in the New Town

Two Walks in Souzay-Champigny

A Gîte Along the Souzay-Champigny Walk

The Green Troglos Gîte in Parnay

A Winery Gîte in Parnay

A Semi-Troglo Gîte with a Troglo Salon d’Été

The L’il Troglo Gîte in Parnay

Tapped Apples

Troglo Shopping Opportunities

Old-Style Cooking in Antoine Cristal’s House

A B&B in Turquant

Cave Swimming in a Stunning Troglo Hotel

A Tasting Room in a Cliffside Manor

Wolf Hill Mushroom Cave and Restaurant

Tasting the Wines of the Loire Valley

Tuffeau Extraction Video and More

Two Walks in Montsoreau

A Château! The Deepest Moat! Caves Everywhere!

A Fortified House That Wasn’t Fortified Enough

Chapter 6: Touraine (Indre-et-Loire) – West and Southwest of Tours

Saints, Hermits, Plantagenets and a Walk above Chinon

Wine Tasting With Rabelais under Chinon Castle

More Wine Tasting under Chinon Castle

A Sculpted Wine Tasting Cave

Great Bourgueil Wine, Great Caves

Find Fossils in a Quarry and in a Museum

A Troglo B&B in a 15th Century Manor

17th Century Farm Caves

Bowling with Finesse

Tapped Pears

A Cave Restaurant near Villandry

Fast-Growing Stalactites, Petrified Plaques and Other Curiosities

Sleep in a House, Swim in a Cave, Ride Away on Your Bike

A Restaurant in Azay-le-Rideau

Two Cave B&Bs in Azay-le-Rideau

In the Valley of the Foxes

Refreshments, Knickknacks and Local Products

Arts, Crafts, Antiques and Basket-Making

A Gîte in Basketry Country

Chapter 7: Touraine (Indre-et-Loire) – The Town of Tours to Montlouis-sur-Loire

Old Saint Martin Had a Cave, and Saint Gatien, Too

A Gallo-Roman Aqueduct in a Wine Cave

A Semi-Troglo Chapel in Rochecorbon

A Sculpted Wine Cave in Rochecorbon

Sparkling Wines and Saint Roch

Zaeli’s Cave of Sculptures

Fine Dining in Rochecorbon

Lodgings in the Cliffs of the Lantern

A Gîte on the Path to the Oppidum

An Elegant Cave Hotel with Restaurant in Rochecorbon

A Walk in Rochecorbon

A Wine Museum with Tasting Room

A Restaurant in the Vouvray Vineyards

A B&B with Belgian Shepherds in Vouvray

A B&B with Sauna in Vouvray

A B&B Cave Suite and More in Vouvray

A Walk in Vouvray

A Winery Co-op in Montlouis-sur-Loire

A Restaurant Next Door to the Winery Co-op

A Restaurant in Southern Montlouis-sur-Loire

Chapter 8: Touraine (Indre-et-Loire) – Amboise and Vicinity

A Château’s Subterranean Chapel

The Cute Troglo Gîte

A B&B in a Château’s Caves

Micha’s Troglo B&B

The Caves of the Green Cross Restaurant

Two Ways to See Caesar’s Storerooms

Two Self-Guided Walks in Amboise

A Fouée Restaurant in Amboise

Chapter 9: Touraine (Indre-et-Loire) and the Vienne – South of Tours

A Walk Near Sainte-Maure-de-Touraine

A Refuge In the Rocks, A Ruined Castle and a Wigwam

Cavemen Drop Knives, Museum Picks Them Up

Cave Walks in Hemp Country

The Music of the Quarry

Cave Pizza Near Loches

Lodgings Near Loches

Chapter 10: The Valley of the Loir (Sarthe, Loir-et-Cher, Eure-et-Loir)

A Snail Farm With Caves

The Poet Pierre de Ronsard’s Manor, Gardens and Caves

Stalactites and Stalagmites in the Making

A Museum of Cave Life in Trôo Plus a Gîte

A Picturesque Troglo Gîte in Trôo

Two Troglo B&B’s on Trôo’s Saint Gabriel Staircase

A Semi-Troglo B&B and Jail in Trôo

A Walk in Trôo

Lodgings Near Lavardin

Karaoke in a Cave and Dinner, Too

Two Walks in Lavardin

A Short Walk in Les Roches-L’Éveque

A Troglo Walk on the Coteau Saint André

The Gîte with a Roof of Irises

A Mushroom Cave Under the Coteau Saint André

Rochambeau, We Are Here

Dining Under Vendôme

Geodes Above the Iridium Anomaly

Chapter 11: The Valley of the Cher (Indre-et-Loire, Loir-et-Cher)

Underground Theater

The Pigeon House Restaurant

A Distillery in the Rock

A Cave Suite in a Château

Mushrooms Are Serious Business in Montrichard

A Miraculous Subterranean Spring and Its Chapel

Silkworms and More above the River Cher

A Walk in Old Bourré

A Restaurant in Two Caves

"The Little Troglo Gîte" in Bourré

A B&B with Sauna in Bourré

A Life-Sized Sculpted Village and a Mushroom Cave

A Cave Restaurant with Terrarium

Addendum: A Few More Gîtes from All Over (Unreviewed)

Special Events

May – The (Partly) Troglodyte Walk/Bicycle Ride at Langeais

Sometimes June, Sometimes May – The Young Winemakers of Vouvray

June – Fouées in the Communal Cave

June - The Big One

June through September – Concerts in the Sculpture

July - Hall of Flowers in a Cave

August – More Wines of Vouvray

September – More Fouées, More Caves

September - Heritage Weekend

December – Subterranean Christmas Markets

Contact Information

Suggestions for Further Reading

Glossary

Index (Alphabetical Order)

Index by Category

Index of Maps and Figures

Author’s Preface

Who does not remember the interest with which when young he looked at shelving rocks, or any approach to a cave? It was the natural yearning of that portion of our most primitive ancestor which still survived in us.

- Henry David Thoreau, Walden, 1854

We didn’t originally plan to live in a cave when we moved from the San Francisco Bay Area to France. And to be precise, not all of our home is in a cave. The house is what’s called semi-troglo in the Loire Valley, short for semi-troglodytique. Located halfway up a hillside along the Loire River, part of it is excavated into the hill and part has been built out from there into the open like a normal stone house. So we’re not full-fledged troglodytes, just partial ones.

At the beginning we knew very little about the region’s rich history of cave dwellings, stretching back in time a millennium or more, so the house, with its strange layout dictated by the contours of the hillside, was a bit disorienting. Recovering quickly from my initial surprise, I pointed out to my wife that there was nothing like this in California and perhaps nothing exactly like it anywhere. It was not quite the same sudden coup de coeur for my indulgent wife, but she went for it anyway, and in time, and after some necessary improvements to the heating system, she has come to love cave living as much as I do.

Once we were living in a cave we started to want to know what other caves of the region were like. How were they formed? What were they used for in the old days? What were they used for now? How did you go about finding them? The search for answers to these questions led me to write this book.

Many thanks to my lovely wife Annette for her support in this project, not least of which were her significant talents as editor.

Thanks to the many proprietors of cave sites who showed me around their establishments.

And thanks to Bernard Tobie, Henri de Fontanges, Caroline Guihard and the staff of Carrefour Anjou Touraine Poitou, past and present, for helping to acquaint me with the strange and wonderful troglodyte world of the Loire Valley.

Naturally, the responsibility for any errors is purely my own.

Introduction - Caves in France?

… the Gauls… are thoroughly familiar with every kind of underground working.

- Julius Caesar, The Conquest of Gaul, 52 BCE

It is not common knowledge, even elsewhere in France, that the Loire Valley, that natural dividing line between the north and the south of France, is riddled with caves. Almost all of them are human creations, cavities hollowed out of the earth in the course of the last two millennia or more. Originally some caves were excavated to serve as refuges from marauders, others as stone quarries, others as mines. Once created, a variety of uses could be found for a cave, not least of which was as habitation.

Of course the French have been associated with caves from time immemorial. France is where the Lascaux cave is located, with its 17,000 year old cave paintings, as well as the Chauvet cave featured in Werner Hertzog’s film Cave of Forgotten Dreams, with paintings going back 32,000 years. And as Julius Caesar noted, the residents were observed to be mining minerals (as well as Roman war constructions) in antiquity. But in the Middle Ages Loire Valley residents started mining the local tuffeau and falun, soft stones that could be easily excavated and from which building material could be extracted.

From this period up to the 17th century entire Loire Valley villages would be situated entirely underground, with nothing aboveground except, perhaps, the church. Cave dwellers were also ubiquitous in rural areas. Perhaps eighty percent of the inhabitants of the countryside in eastern Anjou lived in cave dwellings in those days. Even into the early 20th century a significant proportion of Loire Valley inhabitants still lived underground in many parts of the region.

In earlier times, a broad cross-section of social classes lived in cave habitations, but by the 19th century living in this sort of digs had been relegated to the poor. By the mid-20th century only a handful of cave dwellers hung on underground, and to live in a cave was considered something of a disgrace.

There were other uses for the caves, though, once the extraction of the stone had ceased. Wineries quickly come to mind. Caves were used to make and age still wines, of course, but the sparkling wine industry, established in the Loire Valley in the early 19th century, put large sections of abandoned caves to use for the aging of its product. Mushroom cultivation, also brought to the Loire Valley in the 19th century, was a major industry in the region until fairly recently. A once-thriving silk industry often used caves to raise silkworms.

At the beginning of the 21st century the wineries are still going strong, but most of the other cave-based industries have either died out or have been reduced considerably. Loire Valley caves are now much more likely to be reborn as tourist sites (restaurants, lodgings, museums) or once again, habitation. New technologies and a newfound respect for caves’ ecological qualities have led to a renaissance of cave living. The troglodyte lifestyle appears to have a bright future.

In this guide I’ve tried to include every renovated cave, mine and quarry in the Loire Valley which is currently open to the public, but this is a continuously shifting target. There are more and more cave establishments opening to the public all the time, but there are others which close.

Sometimes the on-site tour or the explanatory reading material will not be in English, or not enough of it will be in English. This can be a frustrating experience for those who don’t speak French. This guide describes for each site the level of English which visitors should expect to encounter. Deficits in English-language descriptions on-site should be compensated for by this book.

Also included in this guide are a number of suggested walks throughout the Loire Valley cave country. That’s where the visitor can see the exteriors of contemporary cave dwellings as well as a good number of abandoned potential fixer-uppers.

At the end of the guide the reader will find contact information for various cave-related organizations and cave country tourist offices. This is followed by suggested reading, including the addresses of several informative websites.

Finally there is a glossary of many of the French terms used in the book, with approximate pronunciations.

This guide will definitely take you off the beaten path. Happy explorations deep in the heart of France.

Map A: France and the Loire Valley Cave Country

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Visiting the Troglodyte World

What’s to See?

This guide is mainly concerned with visitable holes in the earth, only a very few of them natural, in the western and central Loire Valley of France. Most of these are caves started out as underground quarries for the relatively soft tuffeau and falun stone, but also included are a slate mine and open-air granite quarries. Then there are the cave hotels, cave restaurants, cave museums, cave chapels, mushroom farms, even some restored underground villages. And that’s not all.

Since the overwhelming majority of these cavities are the product of the previous millennium, prehistoric humans are hardly mentioned at all in this guide. The caves with their Paleolithic painted walls are mainly located farther south, such as those around the town of Les Éyzies in the Dordogne region. However, our subject area is not entirely devoid of cave-living Neanderthals and Cro-Magnons, as evidenced by finds in the Grottes et Canyon de Saulges and Les Grottes de Foulon, both of which are open to the public and included in this guide. The caves of La Roche Cotard in Langeais show habitation dating back to 45,000 years ago, but not being open to the public they are not included in this guide.

When to See It?

The Loire Valley caves make for great tourism even in bad weather. However, please note that many of these sites are not open in the winter. Check the write-ups of the individual sites for the open dates and times.

What Sorts of Caves Are Not Included in This Guide?

This guide could include about a thousand wineries, since it’s a rare Loire Valley winery that doesn’t have its own cave. So for the sake of brevity, only a handful of wineries have been included, more for the quality of their caves than for that of their wines (although, fortunately for us all, there are some establishments which make very good wines in very good caves (e.g., the Domaine de la Chevalerie). Most of the wineries included here make sparkling wines. This is no coincidence, nor does it represent the wine preference of the author. It is simply that these are the wineries which need the most extensive caves in order to age their product.

While we’re on the subject of wineries, it’s important to point out that you should not get excited when you see a sign saying simply Cave as you’re driving around the countryside. This is the sign for a winery, and they’re not offering a cave tour - they want you to stop and buy some wine.

Some castles have not been included even though they have some underground spaces. This is mainly because the author does not consider those spaces to be a particularly interesting aspect of the visit to the castle. An exception is the Château de Brézé, where the underground section is a major reason for going. For those who want to see hollowed-out spaces while visiting a château, the château of Saumur in Maine-et-Loire has some small dungeons that can be seen during the regular visit. The château of Amboise in Indre-et-Loire has a special tour in the summer months of out-of-the-way and underground areas. The château of Loches in Loir-et-Cher also has subterranean areas which can be visited.

There are also what might be called party caves. These are caves which are rented for special events: wedding receptions, anniversaries, whatever. Such caves may be private, but they also may be owned by the municipality, in which case such as cave is known as the cave communale or cave municipale. Some examples of these latter are the Caves de la Bonne Dame in Vouvray, the Cave Communale in Rou-Marson and the Cave Municipale of Vouvray-sur-Loir. Those that are not open to the public at least for special events are not included in this guide.

The interiors of inhabited cave dwellings are not normally open to the public. However, it is often possible and desirable to see their exteriors. A number of walks are included in this guide to that end. There’s another way to get inside private dwellings (besides befriending the owners). For one slightly frenzied weekend in June (odd-numbered years only) many of the sites listed in this guide are open to the public, often at a reduced rate. In addition, dozens of other sites including private homes which are not normally open will welcome visitors. This is a wonderful opportunity to see what can be accomplished with a once-abandoned cave. The owners, who are more often than not the people who did the restoration work, are delighted to discuss their handiwork, and they speak English more often than one might expect. See Rendez-Vous Troglos, described in the Special Events section of this guide.

You can also stay at a cave gîte or a chambre d’hôte. What’s that, you say? Read on…

Where Are These Caves?

Map B: Loire Valley Departments, Tributary Rivers and Cave Country (in box)

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Just about everything in this guide is found in three departments of the western and central Loire Valley: Maine-et-Loire (the erstwhile province of Anjou), Indre-et-Loire (formerly the province of Touraine) and Loir-et-Cher (note the lack of an e at the end of this Loir – it’s a different river from the Loire with an e).

The Loire Valley generally refers to a river system which includes the Loire River and at least parts of several tributaries, including the Maine, the Mayenne, the Sarthe, the Loir, the Vienne, the Indre and the Cher. In fact, some of the most famous châteaux of the Loire are not on the Loire at all, but instead on one or another of these tributaries.

The hard rock quarries and mines, from which come slate and granite, are located on the western end of the subject area of this guide.

The natural limestone caves, few in number, are located at the extreme northwest and northeast boundaries.

However, the bulk of this guide is concerned with caves dug into two types of soft sedimentary stone, falun and tuffeau. Although falun deposits are found in numerous locations in the Loire Valley, most falun caves are found in a fairly limited area in and around the town of Doué-la-Fontaine (Maine-et-Loire). Falun caves are often described as cathedral caves because of the distinctive shape which their quarrying method produced.

Tuffeau country starts a few kilometers west of Angers and continues about 150 kilometers (90 miles) to the east. There will be tuffeau caves discussed in every section of this guide.

For more on tuffeau and falun, please see the section How Were These Stones Formed?

What’s a Troglo?

Troglo is a word you’ll see over and over in reference to the cave world of the Loire Valley and of France in general. It’s short for maison troglodytique (cave house) or habitation troglodytique (cave habitation), whether currently lived in or abandoned. It’s a useful word to know, partly because the French word cave is more frequently used for a winery or even an aboveground wine store. Thus it’s a lot clearer to ask where the troglos are than where the caves are, unless, of course, you need a drink.

There is also the term semi-troglo. This is a seemingly normal aboveground structure which includes some troglo elements. In current architectural parlance this would be called a partially earth-sheltered home. Usually such structures are built into the side of a hill. From the front they may not look cave-like at all, but once inside there may be walls or entire rooms which are carved into the stone of the hillside. A semi-troglo habitation provides many of the advantages of a full troglo – cool in the summer and warm(ish) in the winter, and the cave portion is a great place for wine storage. It also reduces some of the disadvantages of full troglo, with more light and less humidity, although not all full troglos have either of these problems. There’s a lot of variation in semi-troglo. When this guide discusses a semi-troglo it will always try to describe how interesting or even noticeable the cave features are.

The French adjective troglodytique can be added to anything used by humans that occupies a cave. For example, a chapelle troglodytique (an underground chapel) or a pigeonnier troglodytique (an underground pigeon house).

A cave dweller is a troglodyte. This is not the pejorative term it is in English. In fact, nowadays it’s rather chic, since most troglodytes have taken deteriorating ruins and turned them into interesting and sometimes spectacular dwellings or work spaces. It’s not at all rare to meet former Parisians now living the cave life in the Loire Valley, with all the modern conveniences. (It’s also not rare to meet French people who don’t know when to use the word "troglodyte" and when to use "troglodytique", so feel free to use what you’ve learned here to instruct them in the nuances of their own language, which should be gratifying to all concerned.)

Fittingly, one Loire Valley troglodyte is a former cartoonist for The Flintstones television show.

What Are the Two Types of Troglo Dwellings?

Troglo dwellings of the Loire Valley come in two flavors: troglo de coteau and troglo de plaine.

A coteau (plural: coteaux) is a slope or hillside. In the Loire Valley this term is normally used in reference to the tuffeau cliffs which can rise almost vertically above the Loire or one of its tributaries. A troglo de coteau has to do with a cave which has been cut horizontally into this sort of hillside. A troglo de coteau almost always started out as a quarry.

Figure 1: A troglo de coteau in cross-section

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Figure 2: A troglo de plaine in cross-section

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A plaine is a flat patch of land, a plain. To build a troglo de plaine, the prospective inhabitants had to start by digging a big hole in the ground, usually about eight meters (26 feet) deep, with a ramp or stairway leading down into it. The hole formed a courtyard from which various caves could be cut into the surrounding rock. Fans of Star Wars may remember Luke Skywalker’s home on the planet Tatooine. That is a troglo de plaine, albeit Tunisian rather than French. Unlike the troglo de coteau, which normally started as a stone quarry, the initial purpose for excavating a troglo de plaine was for use as a habitation.

What’s in This Guide That’s Aboveground and Why Is It Here?

A few of the entries in this guide are not really caves, quarries or mines. They have been clearly marked as aboveground attractions and have been included because they’re related to the subject at hand, however tenuously, and because you should not miss them while you’re in the region.

There are also boxes which begin with Speaking of …. In these the author has taken the liberty of going off on a tangent based on something just discussed in the text. These sections are included as an aid to understanding the broader picture, the regional or national context into which some particular cave aspect fits.

Finally, there are the walks. These are for the most part aboveground (with the notable exception of the Souzay-Champigny Walk #1), but they all take the visitor close to caves and cave habitations. Each walk has a starting point and a (very approximate) estimate of how much time it will take. Street names are only mentioned in the walk description if you have a prayer of seeing a street sign at that point. And please remember that most of the caves in this guide are built into hillsides, accessible by paths or very narrow roads, so be prepared to walk up and down a hill or two.

Note that there are a LOT more aboveground, not-to-be-missed sites! It is beyond the scope of this humble guide to steer you toward them, but there are châteaux, churches, villages aplenty. Happily, these aspects of France do not lack for guidebooks.

Geology, Quarrying and Later Uses

How Were These Stones Formed?

The region included in this guide is split between two large geological zones – the Armorican Massif on the west and the Paris Basin on the east.

Map C: Geological divisions of the Western and Central Loire Valley

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The Armorican Massif – Granite, Slate and Schist

In ancient times Armorica was that part of Gaul which included Brittany. The Armorican Massif, occupying what is now Brittany plus other parts of western France, was a mountain range in its day, but its day is pretty much over. After a few hundred million years of erosion, there are no mountains left, just a few hills supported by some very old, very hard underlying rock.

The origins of the Armorican Massif date back two billion years, when the initial stone was deposited. A lot can happen in two billion years. Briefly, this region’s subsequent geological history included metamorphosis of the initial sedimentary stones, more sedimentation and plenty more metamorphosis. Magma intruded deep underground, forming pockets of granite. Around 330 million years ago the movement of tectonic plates caused folding to take place, and this was accompanied by the intrusion of more granite-forming magma into the metamorphic stone. The folding resulted in the mountain range mentioned in the previous paragraph, but when the folding stopped, the mountains eroded away.

What’s left of the Armorican Massif is mainly granite, schist and slate. Schist and slate are quite similar-looking to the lay observer, so similar that this guide will refer to them both as slate. It’s called ardoise in French, and it’s mainly used in slate roofs.

The hard rock of the Armorican Massif plays a very small part in this guide. It appears in the initial section, then quickly bows out once we get a few kilometers west of the town of Angers and into the domain of the Paris Basin.

Between Armorican Massif and Paris Basin: A Short Digression on Coal Mines

There were also coal deposits in the western Loire Valley, found along an axis running from Nort-sur-Erdre in the northwest to Doué-la-Fontaine in the southeast. The deposits date from the Carboniferous epoch, 360 to 240 million years ago. Exploitation started as early as the 14th century and continued up until 1964, although most of the mines had closed by the end of the 19th century. Mine shafts still exist in the area, but since none are currently open to the public, no more will be said about coal in this guide.

The Paris Basin – Tuffeau and Falun

Most of the caves in this guide were carved out of stone deposited in the appropriately named Turonian age, which is part of the Late Cretaceous epoch. Appropriately named because Turonian, which describes a very warm period of the earth’s history from 89.3 to 93.5 million years ago, is derived from Tours, a major city on the Loire. (The name Tours, in turn comes from the Turoni, the Celtic tribe that was living there at the time of Julius Caesar.) The name Cretaceous comes from the Latin word for chalk. This soft chalky limestone of Tours is called tuffeau.

As one travels along the Loire River and its tributaries from Angers in the west to Blois in the east, this cream-colored or light yellowish stone is hard to miss. The châteaux are made out of it, as are most of the old houses, and many of the new houses are at least faced with it.