Keymer used to be a village on its own until it was merged into the modern day village of Hassocks. Keymer's records go back as far as The Domesday Book. Keymer is situated just to the east of Hassocks and is only a matter of a few hundred yards from the boundary with East Sussex. It has a fine parish church unusually called St Cosmas and St Damian Church. The oldest part of Keymer can be found in the area of this church and the Greyhound Pub.