The Signal Box

An excellent web site devoted exclusively to UK railroad signaling standards and rules can be found at The Signal Box.

Excerpt from the site's home page:

This web site is all about railway signalling. Its primary purpose is to describe the principles behind railway signalling in Great Britain, but some coverage of signalling around the world will also be found. The emphasis is on the older, mechanical signalling - that worked by mechanical levers and with semaphore signals. More detailed information on modern and foreign signalling will often be found elsewhere on the web.

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