Grotto / Folly, Montalto Estate, Dromore Road, Ballynahinch, County Down, BT24 8PX

This is a grotto or folly located on the Montalto Estate, approximately 100 metres south of Montalto House near Ballynahinch in County Down. The structure is a somewhat enigmatic, cave-like subterranean opening carved from natural rock. A roughly cut stone stair leads down into the grotto. Its function is unknown, and the current owner has no knowledge of its origins; it is not depicted on any historical maps. It is surmised to be a folly. An Ordnance Survey map of 1834 shows nothing at this location, but a revised map of 1858 marks a summerhouse nearby, a building which has since been demolished and may or may not have had a connection to the grotto. The structure dates to between 1820 and 1839.