THEME: Hadrian’s Wall
The towers along Hadrian’s Wall definitely had communication systems. This was not simply despatching a runner along the wall or a rider behind it, but a way of signalling a message to the next tower along the wall until it could be received by a milecastle or fort, or even sent back, away from the wall, to sites such as Vindolanda or Corbridge. No signal would have to carry far, however. The forts were placed approximately twelve kilometres (7.5 miles)
