Nore Folly (also known as Slindon Folly) is a stone construction located near the village of Slindon, West Sussex, United Kingdom. The folly resembles a gateway but is a decorative piece which leads to nowhere. It was built of flint in the 18th century by the Newburgh family, possibly due to the countess's liking an Italian picture of a building.
The National Trust, which restored the folly in 1993, states that Nore Folly was "built in 1814 for the Countess of Newburgh’s picnic parties". At that time there was a small covered building attached, which has since been torn down. It has been designated as a Grade II listed building.
A well-used, although somewhat steep, walking path leads up to Nore Folly, at which there is an outlook with a clear view over the countryside, including a view of Halnaker Windmill, a long section of the coastline, Portsmouth Spinnaker Tower, Chichester Cathedral, and Bognor Regis.
The folly has been featured on a first day cover designed by British First Day Covers Limited in 2006.