Ayers House is a historic mansion in Adelaide, South Australia located on North Terrace. It is named after Sir Henry Ayers, five times Premier of South Australia and wealthy industrialist, who occupied it from 1855 until 1897. It is the only mansion to have survived on North Terrace.
Internally, the rooms of the mansion feature hand-painted ceilings, stencilled woodwork and contain memorabillia from the Ayers family, demonstrating the wealth of the property at the time it was built. Sir Henry also commissioned the building of a basement to allow him to escape the hot Adelaide summers.