Heritage Open Day: Nutley Windmill is a rare example of an open trestle post mill, which is only open on a limited number of days. This special opening for Heritage Open Days gives an opportunity to see this fascinating building. Nutley Windmill is probably the only open trestle post mill in the country capable of working. The main post is over 300 years old but the design of the building goes back to the 12th Century, the earliest wind mills in this country. Sited in Ashdown Forest it is run by volunteers from Uckfield Heritage who have restored and maintained the building. This Heritage Open Day is an opportunity to see the machinery inside the building and hear information from our expert guides.