A strong fishing industry and booming, prosperous granite quarries in the area made the Deer Island Thorofare a busy waterway in the 19th century. The lighthouse on the west side of Mark Island guards the western approach to the Thorofare and was built in 1857 to help mariners negotiate the waters near Stonington. A 25-foot square brick tower was constructed and the tower fitted with a fourth-order Fresnel lens; keeper's house, bell tower, oil house and boathouse also were added.
The light was automated in 1958 and the Fresnel lens replaced by a modern optic. All buildings except the tower were destroyed. Although visible distantly from the mainland, the light should be viewed by boat. It is now owned by the Island Heritage Trust.