The Lammas harvest celebration is related to the Lammas Fair. The Ould Lammas Fair (as it is known) is one of the oldest fairs in Ireland, stretching back over 400 years to the 17th century. It takes place on the last Monday and Tuesday of August in Ballycastle, Northern Ireland. Usually, a lot of different things are sold at the fair. These include livestock as well as traditional dishes like Yellowman, a local variation of honeycomb, and dulse, a form of edible seaweed.