There's a lovely little unembeddable video here about Bush House, from where the BBC World Service has broadcasting since 1940. It reminded me of a tiny little career I had turning up there every few weeks to be 'presenter's friend' on Culture Shock. (Which has disappeared without trace and turned into this stub).
We used to record at very odd times of the night and the best bit was always wondering around this strange old building - simultaneously gilded and shabby, like a manor house taken over by engineers and artists.
(I loved these - these were doors used to make door sounds on radio dramas.)