Escape tunnel

An escape tunnel is a form of secret passage used as part of an escape from siege or captivity. In medieval times such tunnels are usually constructed by the builders of castles or palaces who wish to have an escape route if their domain is under attack. In the case of prisoners, escape tunnels are dug to be free of captivity.

In road and rail tunnels, narrower escape tunnels are provided to enable people to escape on foot in the event of a fire or other accident in the main tunnel. For example, between the two main bores of the Channel Tunnel is an access tunnel large enough to take a fire engine.

Throughout the British Isles and much of northern Europe escape tunnels were often part of the intrinsic design of fortified houses and palaces. The tunnel would typically be one half to two kilometers long and open in a location not readily visible to attackers. Examples of these tunnels are at Muchalls Castle (Scotland) and the Bishops Palace at Exeter (England).

The following escapes were at least a partial success, with prisoners escaping via tunnels:

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