Heritage Open Day: Discover inside the unusual octagonal Albury Pigeon house, built in the 16th century when pigeons were used for food, and their droppings for gunpowder. Enter and see the potence (the rotatable access ladder) and the 649 pigeon holes. Albury Pigeon House is an unusual eight-sided brick built structure with a pyramidal roof containing four dormer 'porches' each with a pair of entrances. The building is surmounted by a lantern, the top of which is about 35 feet from the ground. Inside there are over 600 nest-holes and a potence. This is a structure consisting of a vertical central post, pivoted at the top and bottom, from which horizontal beams project. These support a ladder which gives access to the nests.