Sky Garden at 20 Fenchurch Street — the Walkie Talkie — is the most accessible rooftop view in London. The 360-degree garden bar at the top of the building is open to the public with free pre-booked entry. Once inside, you order at the bar.
The cocktails are mid-priced and well made for the venue. The view is the headline. The bar opens at 7am for breakfast and runs through to 1am, making it a rare all-day rooftop in London.
The crowd is overwhelmingly tourist for the photo opportunity. Locals come for breakfast and early evening drinks. Best for sunset on a clear London evening. For more focused cocktails with a similar view, Aqua Shard across the river is the more polished option.