If you must go to London, it’s always worth taking a wander along the South Bank, past the Royal Festival Hall and either upstream towards Westminster, or east towards the Tate Modern and Borough Market.
This is roughly half way between the two: the Queen Elizabeth Hall, part of the South Bank Centre. The cable car-like structure balanced on top of the building is actually supposed to be a ship. It’s a one-room hotel for which there’s a ballot to decide who gets a chance to stay there for a single night.
Meta: Canon EOS 5D Mk III, 1/60 sec at f/8.0, 32mm, ISO 100.