Historic England The number of at risk sites in London listed by Historic England has remained almost the same at 604, after 20 were saved and 21 new ones were added, after being identified as needing restoration. New at risk sites include Hampstead Heath's Hill Garden Pergola and the conservatory at Chiswick House. The once derelict Bruce Grove public toilets, in Tottenham, north London, and Upminster Tithe Barn, in east London, are among those brought back into use by the public body.