The name hypocaust comes from a Greek work meaning “fire beneath”. This was a common form of central heating used by the Romans. A fire would be lit below the fortress baths to heat the water, using air ducts to transfer the heat around the building and keep it warm.

A hypocaust remains visible below one of Chester’s high street buildings, discovered in 1725. The building is now a restaurant “Spud u Like”, allowing customers to view the Roman remains.