Archive:Utility tunnel
A utility tunnel is a subterranean space for wires, conduits, pipes, and other conveyances used in the delivery of utilities with enough room for a human to enter. Modern pipes and cables need less attention than older varieties, so the construction of utility tunnels has declined of late. Modern underground utilities tend to be enclosed in pipe chases, which are (by definition) not large enough for people.
Steam pipes, in particular, tend to be housed in large tunnels for easy access by workmen. A number of university campuses have a complex network of steam pipes; student exploration thereof is referred to as Roof and tunnel hacking.