Before European Settlers arrived in Pennsylvania, a deep forest of hemlock, white pine, ash, hickory, elm, oak, cherry, and American chestnut covered the Locust Valley.
The Lenni Lenape claimed the land, then it was conquered by the Susquehannocks, and finally controlled by the New York Iroquois League of Five Nations.
When settlers discovered anthracite coal in Schuylkill County, immigrants swiftly arrived for the mining jobs reaching the Locust Valley in the mid-1800s. It was not economically feasible to mine the coal in the Locust Valley, but the area did not escape the American Industrial Revolution.
The forests fell to the logger’s ax as sawmills turned the trees into lumber, shingles, tool handles, and other wood products. Tanneries crushed hemlock and white pine bark for tanning leather. Colliers burned chestnuts and oaks into charcoal. Strong timbers supported the roofs of mines. The forests were gone by the early 1900s, replaced by shrubby land prone to seasonal floods and forest fires. Some farmers tilled the cleared land.
Purchased by the Marshalonis Brothers, the Locust Lake area became a fishing spot and picnic grove. When digging a lake, the brothers found a dam, boards, and the hub of a waterwheel under seven feet of leaves, silt, and debris. The remains of an old logging mill and dam were buried under silt from flooding and runoff caused by the removal of all of the trees for lumber during the logging era.
The Commonwealth of Pennsylvania purchased the Marshalonis Brothers land in 1966. Locust Lake State Park officially opened on June 10, 1972.