The mill (converted to a residence) is located on Williston Lake, Mill Creek (formally Coquericus or Cokiases Creek and later Phillips Creek), a branch of the Choptank River. The millstone is still in place. There was no external waterwheel.
The mill was leased by James White to Nathaniel Potter as early as 1778. The mill was rebuilt (possibly in a different location) by General William Potter who started, but apparently never finished, a ship channel from the Choptank River to the mill (McGrain, J. Molinography of Caroline County). Subsequent owners were S. Liden (1875, Isler map) and William Todd (1897, Saulsbury map).
Colonel John Arthur Willis purchased Potter Hall shortly after the death of William Potter; thus the name Williston Mill. Willard C. Todd called it Williston Mill when he operated the facility in the 1920s. He installed rollers and sold the mill's hominy equipment to Frank Langrell, his miller, who re-installed it in Linchester, which he operated for over fifty years. The mill suffered flood damage in 1919, losing 20 to 30 feet of the dam. The mill stands in the yard of Todd's former house, a peg structure that was disassembled and moved.
The present mill building is composed of two separate structures, one dating from the early 19th century and the other from the late 19th century. The mill was originally an undershot wheel and apparently had a turbine prior to being shut down. A painting of the mill hangs in the Caroline County Clubhouse. The present MD Route 16 crosses in front of (immediately below) the dam which forms Williston Lake.