Panama Rocks

You can read the direction of a vanished river here. Rivers flip stones as they roll them, always tipping them the same way relative to the current, and the pattern is called imbrication. The stones locked into the rock at Panama Rocks are tilted consistently enough to show that the current ran south to north in today's orientation, which the park puts down to a bend in the river plus a few hundred million years of tectonic rotation since.

The rock is quartz conglomerate, sometimes called pudding stone, and the formations run half a mile long and sixty feet high, among the largest exposed examples of glacier-cut ocean-quartz conglomerate anywhere. The material dates to roughly 400 to 350 million years ago. That is older than the dinosaurs and about as old as the first trees.

The sequence is worth following. In the middle Devonian, 385 million years back, the core of North America sat rotated ninety degrees and straddled the equator, and what is now upstate New York, western Pennsylvania, eastern Ohio and Lake Erie lay under a shallow sea called the Appalachian Basin. The stones here were its shoreline and bottom. Around 347 million years ago the late Devonian extinction removed roughly half of all genera. Then, as Pangaea assembled, the land under the basin rose and drained it through big meandering rivers between 320 and 310 million years ago, and calcite cemented their gravel like natural concrete.

Fossils are scarce, and the park explains why: the current was strong enough to wash out the lighter mud and silt, and the marine animals of the day were poor swimmers. Brachiopods, crinoids, radiolarians and syringopora do turn up.

The trail runs 10am to 5pm daily with last admission at four. Day passes in 2026 are eleven dollars general, eight for children six to twelve, nine for veterans, serving members and over-65s, free under six, and there is a lower-income access pass.