Sidney Flat
Black Diamond Mines, Antioch    
Mike Medeiros

Sidney Flat
This area was the original site of the coal mining town of Somersville. The town was located here because
of the availability of good drinking water. When the railroad arrived in 1866, water could be hauled from
the San Joaquin River and the town was moved closer to the mines. A rancher later established a brothel
here that included the unusual feature of a tunnel connecting the building’s rear entrance to a nearby ravine,
allowing customers to avoid being seen by passers-by.
1n 1904, the land was sold to coal field residents Leyshon and Lizzie Lougher whose family remained on the
land until 1956. Leyshon used materials salvaged from structures in the abandoned coal mining town of
Nortonville to construct the house located across the road. A sheep barn and baseball field were built
where the park headquarters now stand. In 1977 Sidney Flat was purchased by the East Bay Regional Park
District and became part of Black Diamond Regional Preserve. The ranch is currently used as the park residence.

Dedicated November 2, 2002
Jointly sponsored by
Joaquin Murrieta Chapter No. 13 E Clampus Vitus
and the East Bay Regional Park District