London Photo Gallery - The City's New Observation Decks

Several new skyscraper projects are transforming The City's skyline. Within these projects tucked away on a high floor are free observation decks that you need to pre-book online. It's not just the Walkie Talkie building's Sky Garden that is offering a great view anymore. The Lookout is located on 8 Bishopsgate's top (50th) floor. Facing the Thames on 2 sides only, I'm just across the street from 1 Leadenhall's construction site. The highlight is the Tower of London, although it's not really possible to see Canary Wharf directly as the windows face south and west only.
120 Fenchurch has a rooftop garden that is open to the public for free without the need to book online beforehand. It covers all 4 sides of the building, offering views of Canary Wharf, the Tower of London, St. Paul's, and the Shard, although it is not as tall as Sky Garden.