One of the best ways to see the complexity of the Crystal Palace's con-struction was from the air.

Originally symetrical in plan, the loss of the North Transept in 1866 is clearly visible in this view.

In the distance Dulwich appears semi-rural.

By 1920, London's suburbs had reached Orpington, several miles further out from the centre, but the low density of development around the Sydenham Hill area is evident from this photograph.