Where: Cannon Bridge Roof Gardens
There are secret gardens aplenty in the capital, as long as you know where to look. In this case, you need to go up in a lift via an office block on Cannon Street, then walk up a spiral staircase. The garden has hosted croquet and private champagne receptions, and a marquee provides shelter for drizzly days. There are fantastic views over the Thames, the Shard and Tower Bridge, among many other landmarks.
