Eye Castle is a motte and bailey medieval castle with a prominent Victorian addition in the town of Eye, Suffolk. Built shortly after the Norman conquest of England in 1066, the castle was sacked and largely destroyed in 1265. Sir Edward Kerrison built a stone house on the motte in 1844: the house later decayed into ruin, becoming known as Kerrison's Folly in subsequent years.

This was formed of the land held by Robert Malet at the time of the Domesday Survey, and it probably constituted part of the endowment of the Priory of Eye when he founded that establishment. The following is taken from a MS. in the writer's possession: " The manor of Eye Thel- netham is parcel of the Honor of Eye and comprehended in the value thereof. In the gross sum of the perquisites of Courts the reliefs arising from Castleward tenants are valued at 15/1. per annum. This particular is grounded upon a survey taken by Thomas Jackson gent, and others in the month of September 1650 and is made forth, examined and signed by order of the contractors 25 September 1650. John Weekly, Deputy Register."

The manor seems to have been vested in Charles Marquis Cornwallis at the time of his death in 1805, and then passed to his son and heir Charles 2nd Marquis who died without issue in 1823.' It was purchased by Matthias Kerrison of Bungay in 1825. Matthias Kerrison married Mary, daughter of Edward Barnes, and died in 1827, when the manor passed to his only son Sir Edward Kerrison, and then followed the course of descent of the main manor of Thelnetham.