Caesar Creek spillway

Four rules, and they are worth memorising before you drive out. No tools. No collecting for commercial use. Everything you keep has to fit in the palm of your hand. And all collecting must happen inside the designated fossil collection zone. Stay inside those and Caesar Creek is one of the most straightforward places in Ohio to fill a pocket legally.

The palm-sized limit is the one that catches people, and it is a sensible piece of design. It rules out the slab-hauling that strips a site bare while leaving the small, complete, genuinely interesting material for everyone else. The no-tools rule works the same way: what the spillway hands you is what weather and water have already loosened.

The spillway itself exists because the U.S. Army Corps of Engineers dammed Caesar Creek in the 1970s, impounding a lake of 2,830 acres. Cutting that channel exposed the rock, and the park now leased from the Corps by the state runs to 7,530 acres including the water. It sits five miles east of Waynesville, spread across Warren, Clinton and Greene counties.

Give yourself a reason to stay. There are 43 miles of hiking trails and 31 miles of bridle trails. The nature center, renovated in 2025, carries exhibits on the park's fossils along with water quality and local ecosystems, and it is worth calling in first to see what you are looking for; a dozen outdoor labs surround the building. It keeps short hours, Thursday afternoon through Saturday, so check before relying on it. The park is also a certified firefly habitat, which is a good argument for staying until dark.

Next to the nature center is Caesar's Creek Pioneer Village, more than fifteen log buildings including a Quaker meetinghouse, a blacksmith shop and a toll house, run by a non-profit and open during special events.