NEHL - This is one of the multiple drifts and shafts which were presumably worked as part of the Sunniside Colliery complex in the 19th century. Beneath the River Deerness there were 2 drifts alongside the footpath towards Low West House, with another shaft on the north bank of the river. Due to the proximity of Sunniside Colliery, it is probable Pease opened these drift mines and shafts to allow access and ventilation to the workings.