Built in 1766 in the design of The Temple at Castle Howard in Yorkshire. It is said that Lord Delaval had the building erected in honour of his only son, John, who died in 1775 aged 20. Evidently he died of complications arising from having been kicked in a vital organ by a laundry maid who he was giving unwelcomed attention. The mausoleum was not used by the Delaval Family and is now in a ruined state, although in its heyday it must have been a fine building with a leaded glass dome.