Bath (/?b???/ or /?b??/; Latin: Aquae Sulis, Welsh: Caerfaddon), is a cityin the ceremonial county of Somerset, England, known for its Roman-built baths. In 2011, the population was 88,859. Bath is in the valley of theRiver Avon, 97 miles (156 km) west of London and 11 miles (18 km) south-east of Bristol. The city became a World Heritage Site in 1987.