The London Open House weekend was a bit less exciting than I hoped. To my mind, a building isn't really open if you are only allowed into the lobby, especially if it has big glass doors so that you are not really seeing anything you couldn't see from the street anyway! This happened to us twice - at the Daily Express building on Fleet Street, and at 100 Wood Street. City Hall on the other hand was brilliant. A fantastic view from the top, and a vertiginous walk down the extraordinary staircase that spirals slantwise down the building, with bird's eye views of the council chamber. And the basement was fascinating too - crowds of people, some on hands and knees, exploring the floor which is tiled with a huge aerial photo collage of Greater London. Well worth the queue.