 The Civilian Conservation Corps ( CCC ) improved access and constructed many of the amenities at Leonard Harrison park from 1933 to 1936 , during the Great Depression . Leonard Harrison State Park is one of many examples of the work of the CCC throughout north @-@ central Pennsylvania . The CCC built picnic and comfort facilities , made roads and trails ( often following old logging roads ) , and planted stands of white pine , spruce and larch . Some of the CCC @-@ constructed facilities remain and are still used , and the park has hosted a reunion of former CCC workers each summer since 1990 . 
