Lazy line moorings can seem complex, but they are actually quite a simple solution, especially in busy harbours. Large concrete blocks, or massive chains are laid out parallel to the quay, in front of the berths. lazy lines are attached to these, then usually tailed back and tied on to the quayside where they can be easily accessed. When not in use the lines lie along the seabed, out of the way of boats, hence the alternative name ‘slime line’.
Essentially a lazy line gives a more permanent, secure option to Med (or stern-to) mooring with an anchor. When well-tensioned off the bow of a yacht, a lazy line will hold the boat off the quay, even in strong winds; at Sail Ionian