Icehouse Approximately 35 Metres South of Postern, Hertford Castle (Hertford Castle Demolished)

The icehouse, built around 1795 to 1800, is located approximately 35 meters south of the Postern at Hertford Castle, which has since been demolished. It is constructed of red brick in header bond and features a subterranean chamber with an earth mound above. Access is gained through a reset-iron gate beneath a modern concrete slab, leading into an arched entrance. The structure has a dogleg plan, measuring 4.7 meters long, with a red brick floor and a segmental arched roof. Inside, there are four frame rebates that lead to a circular well approximately 3.5 meters in diameter and 3.2 meters deep. The well has a hemispherical domed roof made of header bonded brick and a conical lower section in English bond. Although the brickwork is discoloured and calcified, it appears to have originally been red. The well features a lip at the end, creating a small access hole, and the well door is positioned sloping over the well. A small window has been cut into the left wall of the entrance tunnel between the second and third doors, but its purpose is unclear as it now only reveals the surrounding earth mound. The construction of the icehouse took place on the thin islet between the two historic castle moats, during major alterations carried out by the Marquis of Downshire in the late 18th century.