Visited with Userscott. If you can say one thing about this former air-raid shelter, landing stage and public bogs, it's that it's rather hard to get in.
The most interesting features are perhaps the remnants of the WW2 shelter. Posters on the walls, painted signs and a substation room. Throw in lots of steps, corridors, little rooms and offices tucked away, and then the huge gents toilets, and you've got a real treat.
Getting out was just as tricky as getting in, and by the time we emerged we were covered in grime and muck, but it had been worth it. Unfortunately the search blaster failed pretty early on, so we had to use the head-torches and remote flash for most of the photos, but they came out ok.
Big thanks to Scott for leading this one, and of course to him and stepping_lightly for cracking it in the first place.