There's a strange avenue of trees in Richmond Park, ten miles from St Paul's Cathedral; and an odd, wedge-shaped skyscraper in the city. At the New London Model, at the NLA Galleries at the Building Centre, I explain both of these. London is going vertical: but there are quite a few places where tall buildings aren't allowed, and here's why. Thanks to Dan W on camera, and to the team at the New London Model!