Carshalton built a number of air-raid shelters in the years leading up to World War II. Like many local authorities, local parks were often used and Carshalton Park was one such site. The shelter there was intended for 1,000 shelterers.
In January 2012, the shelter was rediscovered when a hole appeared in the park. The shelter beneath proved to have originally had three stairway entrances and five emergency exits. Built as usual by cut-and-cover, the shelter had electric lighting and the remains of stoves for heating were also discovered. There were separate male and female toilets and (unusually) these connected with mains sewerage rather than being chemical ‘Elsan’ toilets.
The article in Subterranea gives a plan and some photos of the site dating from 2012.