Horizon 22
City of London, 22 Bishopsgate
The highest free viewpoint in the city — 58 floors up behind floor-to-ceiling glass, with views stretching to Buckingham Palace on a clear day and zero entry fee.
💡 It needs a free timed ticket that books out fast, so tickets drop on Mondays; if it's gone, Garden at 120 down the street is a walk-in backup with no booking.