At the vast majority of fossil-related parks, you can look but never touch. That may be good for the treasures that the parks protect, but it's not the best for getting people involved. Fortunately, most common fossils are not rare, and a scattering of parks allow the public to dig for fossils. If you know of a park that's not listed here, contact me at geology "dot" guide "at" about "dot" com.
The Waynesville area, in the heart of the Cincinnati Arch, yields abundant Ordovician fossils including brachiopods, bryozoans, crinoids, corals and the occasional trilobite. The US Army Corps of Engineers allows fossil collecting in the Emergency Spillway near the Caesar Creek Dam. You need a free permit from the visitor center, you may not use any tools, and anything larger than the palm of your hand goes to the Visitor Center's collection.
USACE Caesar Creek Lake website: find fossil information under Recreation.
Noteworthy plant and animal fossils from Early Cretaceous times have come from the quarry here since the mid-1800s, including specimens of Maryland's state dinosaur,
Astrodon johnstoni. Every first and third Saturday of the month from noon to 4 p.m., the public can help the pros as they explore this precious scientific site.
Park websiteThe rocks exposed in the emergency spillway of the dam at William H. Harsha Lake are 438 million years old (Ordovician). Fossils are predominantly brachiopods and bryozoans. The US Army Corps of Engineers permits fossil collecting there as long as you use no tools and leave behind any specimen larger than the palm of your hand.
USACE Harsha Lake website: find fossils under Recreation + More Recreation Information.
Fossil Butte preserves a small portion of the enormous
Green River Formation, an ancient freshwater lakebed some 50 million years old (Eocene). On Fridays and Saturdays during summer, visitors can help park scientists dig for fossils on a strictly catch-and-release basis. The program is called "Aquarium in Stone."
Fossil Butte ranger programs pageFossil Park, Sylvania, OH
Soft Middle Devonian shale of the Silica Formation is brought here from the Hanson Aggregate quarries for the public to pick over using only their hands. Trilobites, horn corals, brachiopods, crinoids, early colonial corals and more are found there. It's a popular school outing, complete with lesson plans and a geologist-authored field guide. There's no charge. The pit is open from late April to early November.
Park websiteThe Ordovician fossils of this area may be collected at two "fossil collection areas" shown on the park map (the
fossil pamphlet shows more). Inquire at the Park Office before digging. During summer months, the park naturalist leads fossil hunts.
Park websiteLadonia Fossil Park, Ladonia, TX
Sediments in the bluffs of the North Sulphur River near Dallas yield all kinds of Cretaceous fossils from mosasaur bones to ammonites, bivalves and shark teeth. The Pleistocene sediments above have mammoth bones and teeth. This is a rugged, at-your-own-risk kind of place where you need to watch for snakes, slides, feral pigs and sudden floods from controlled water releases.
Park websiteLafarge Fossil Park, Alpena, MI
The Besser Museum for Northeast Michigan, near Thunder Bay in Lake Huron, hosts this site where the great Lafarge Alpena quarry contributes raw Devonian-age limestone for the public to explore. The museum's website has no information on the fossils, but it shows a nice coral specimen. Open from dawn to dusk year-round.
Besser Museum websiteMineral Wells Fossil Park, Mineral Wells, TX
A former borrow pit for the city of Mineral Wells now gives visitors a chance to collect fossils from the 300-million-year-old (Pennsylvanian) shale. Open all day Friday through Monday at no charge, the site yields crinoids, bivalves, brachiopods, corals, trilobites and much more. The Dallas Paleontological Society has a volunteer program for this unusual public resource.
Park websiteThe city of Fairborn, near Dayton, allows fossil collecting in this former limestone quarry; you'll find brachiopods, crinoids and other Silurian marine fossils. The site map also points out glacial grooves and a (fossil) coral reef. Check for instructions when you arrive.
Park map