Gallows Conduit House (In Grounds of Hampton Spring)

Gallows Conduit House in Kingston upon Thames is a rare surviving conduit house dating from 1538-40, constructed as part of a water supply system for Hampton Court Palace. It stands on George Road, in the grounds of Hampton Spring.

The building comprises two separate structures: a lower chamber and an upper chamber, joined by an underground pipe or culvert. The lower chamber is a rectangular single-storey building constructed of red brick with stone dressings and a steeply-pitched tiled roof. Its south elevation features a square chamfered head doorway with chamfered jambs. The building sits on a brick plinth which carries, on its east side, what appears to be a decorative motif formed by black headers reading V-T-V. The window dressings are of gauged brick and date from the late 17th or early 18th century. The upper chamber, situated to the north, is a small brick vaulted building that originally covered the spring.

The interior of the lower chamber displays recessed brick arches in its walls and a small cupboard opening. The roof contains some original timbers, though the floor is now modern concrete. The original lead cistern may survive beneath it. The upper chamber is currently inaccessible but was recorded in a 1900 survey as measuring approximately 2.1 metres long by 1.5 metres wide, with a narrow rectangular water tank served by at least five feeder pipes.

Following King Henry VIII's acquisition of Hampton Court Palace, a greater water supply was required than the existing conduit at Hampton village could provide. After the suppression of Merton Priory in 1538, land was set aside in upper Kingston for a new system. Constructed between 1538 and 1545, Gallows Conduit House was one of three surviving conduit houses (alongside Coombe Conduit and Ivy Conduit) built to collect water from springs at Coombe, approximately 5 kilometres to the north-east. The water travelled under gravity through underground lead pipes to the Palace, passing beneath the rivers Hogsmill and Thames via several tamkin houses—small brick structures with stopcocks and expansion tanks that facilitated maintenance and leak detection. Gallows Tamkin, one such structure, still survives. The conduit house itself gained its name from its proximity to the local gibbet or gallows in the 16th century, and is depicted in a detailed plan of the Hampton Court conduit system drawn by Thomas Fort in 1742.

Records indicate repair work was undertaken in the early 17th and early 18th centuries. In 1742, the Office of Works commissioned a survey and carried out a major overhaul to increase efficiency. The system continued to supply Hampton Court Palace until 1876.