I do like a hammerbeam roof! The lower half of the room is kinda boring in comparison, but it does make it a flexible space for exhibitions and conferences etc.
It's a weird fact that most of the 10,000's of people crossing London Bridge don't realise, but there's squash courts under the left-hand end. I guess they must have once been part of a corporate gym for the adjacent offices, but it's now run by a chain, I used that gym sometimes when I lived a few minutes from there (but I preferred its above-ground sibling at the other end of the bridge).