7 Bishop’s Road, Lisnagrib, Limavady, Co Londonderry, BT49 OJN

The property at 7 Bishop’s Road, Lisnagrib, Limavady is a single-storey vernacular house built between 1920 and 1939, though incorporating a pre-1831 structure. It is of historical interest due to its location above a subterranean cavern or souterrain.

The house is an asbestos-slated cottage, entered through a narrow hall running from front to rear, with a kitchen in the back return. It is gable-ended with chimneys on each gable and one between. Originally a direct-entry dwelling, the purpose of the rooms has been altered, with the addition of gabled back returns also roofed with asbestos slates. The external walls are dry-dashed with black and white stones and cream-coloured plaster, and the windows have narrow reveals. The windows are wooden, with four-pane sliding sashes. The primary interest lies beneath the house, in the cavern which originally had an entrance in the west gable. According to the owner, this cavern extended back under the house and then turned at right angles under the back return. A reinforced concrete floor now covers the cavern, placed during previous improvements to the house.

According to the Ordnance Survey Memoirs, the cave entrance was about 15 years closed at the time of the record, and would have allowed a man to stand upright. Thomas Johnston explored the cave approximately 10 yards before being blocked by fallen stones, which revealed regularly laid stonework suggesting further chambers. It was believed to extend approximately 20 yards, possibly with rooms extending under the dwelling house. A decayed wooden dish and a turned stick were found within. A former proprietor, William Johnston, stated this. The current owner does not know if a Johnston formerly lived in the house, having inherited it from their grandfather. The present house was constructed on the demolished walls of an earlier building during the 1920s, during which time an earthen hearth wall was discovered.