The park sits on the Frontenac Axis, a southerly extension of the Precambrian shield that divides the St. Lawrence lowlands in two. This division gives rise to the Thousand Islands and the Adirondack Mountains of New York State. Geologists have long been fascinated by parts of the Frontenac Axis, where the rock often reflects two major geological periods, each separated by vast lengths of time.

According to geologists, the area was once the boundary between two ancient bodies of water -- Lake Iroquois to the southwest and the Champlain Sea to the east. On scheduled hikes, park interpreters will point out intrusive granites, metamorphic gneisses, and other samples of the older rock that originated in the Palaeozoic era. They tell how these layers were twisted, folded, and deformed from the intense heat and pressure of the earth.

The park also features lowland forests, hemlock ridges, lush wetlands and the picturesque, rocky shoreline of Lake Charleston. Zoologists and biologists have noted many plants and wildlife in this region either beyond the normal southern or northern extent of their range.