A disaster overtook skaters on Regent's Park lake in London on 15 January, 1867 when the ice gave way, plunging 500 people into 12 feet of water. Bystanders tore branches off trees and launched boats drawn up on the banks as spectators turned into desperate and valiant rescuers.
Many skaters clinging to broken pieces of ice, or able to stay afloat in the icy water, were pulled to safety. However a total of 40 people died in the tragedy, dragged down by their heavy skates. There had been a break in the ice the previous day when 21 people had fallen through, although all of them were rescued. As a result warning notices about the dangerous conditions had been posted, but the enthusiasm for the sport among ordinary people was so great that these were ignored.
The skaters were blamed for their own misfortunes. However, it was also noted that the park keepers, concerned about the welfare of the important collection of water fowl on the lake, had been breaking the ice around the edges to provide open water for the birds.
A light fall of snow had disguised the cracks and the weight of 500 people had caused a sudden catastrophic collapse of the frozen surface. This was said at the time to be the worst weather related disaster in Britain. As a precaution against a similar tragedy ever happening again the water was drained and the lake bed raised with soil and concrete, so the lake is now only four feet deep.