Aside from the tarmacadam surfacing and modern shelter, the site remains unchanged since opening. A plant to manufacture tarmacadam was built beside Whitstable Harbour in 1936. The square was originally surfaced with tarmacadam, which was replaced with stone in the 1920s. Outdoor ranges with a covered firing point are usually concrete or tarmacadam. A tarmacadam plant was also built, operating from 1936 to 1948.