If you want to see something that is never publicised, but which is astounding, then make tracks for the Wellington Quarry. It's WW1, but the French have done what they do best, and turned the place into an incredible tourist attraction.
http://www.webmatters.net/france/ww1_ar ... ington.htm
The website does not do it justice, you get a seat in a surround screen cinema, drop down hundreds of feet in a glass walled lift, and the tour takes ages. Everything is preserved, and the engineering feat performed by the Kiwi's has to be seen to be believed.
...and where in Bristol are you? That's where I am from????
Cheers
Rob G