The Trackside pub at Bury Bolton St (East Lancs Railway) always has some railway themed ales for obvious reasons. More-so when there is an event on.
"Deltic Diesel" (as already mentioned) is exceptionally popular and tastes excellent.
"Sulzer Slayer" is a mighty fine ale too
There is also "Ernest Ale" which I'm not sure on the history of but either way we have it due to our Class 14 being named "Ernest"
There was a rather dark ale or stout with Black Five in the name (can't think of it right now)
The above are all guest ales which are rotated quite well so do find themselves back on around every month/two months or so.
Piston Broke - aside from being a clever play on words is a permanent one, simple and yet very nice.
There is also the railway's own "East Lancashire Railway Ale" which is exceptionally nice.
Needless to say all of the above are very easy to drink and I have tried drinking my body-weight in all
Phil