Rockport Recreation Area: Fossil Hunting in Alpena County, Michigan
Updated August 2026
Rockport State Recreation Area opens a 300-acre former limestone quarry whose floor is scattered with Devonian fossils about 400 million years old, including Petoskey stones, Favosites honeycomb coral, brachiopods, and crinoids. It is one of the few Michigan state sites where the DNR openly invites visitors to keep up to 25 pounds of fossils per person each year. Pyrite also occurs in the quarry beds. Reported finds include petoskey stones, fossilized coral, brachiopods, crinoid stems, pyrite, and more. Below: coordinates, access notes, nearby spots, and trip-planning links.
Rockport Recreation Area photos
Public image records connected to this spot or its reported material.
Map showing Rockport Recreation Area in Alpena County, Michigan
Quick details
- Access
- Public area
- County
- Alpena County
- State
- Michigan
- Nearest road
- Old Grade Road
- Coordinates
- 45.20126, -83.39488
Geology at Rockport Recreation Area
This spot sits on Traverse Group, mapped as limestone that formed roughly 395 to 385 million years ago. Limestone like this typically forms in ancient seas, so marine fossils such as brachiopods, corals, and crinoids tend to weather out of fresh exposures.
- Mapped unit
- Traverse Group
- Age
- 395–385 Ma (Middle Devonian)
- Rock types
- limestone
- Elevation
- 600 ft
Geologic mapping via Macrostrat and the underlying state geological survey maps (CC BY 4.0). Bedrock at the surface can vary within a mapped unit.
Best time to visit Rockport Recreation Area
Best months: April to October. Typical highs run 77°F in midsummer and 27°F in midwinter, with winter lows near 13°F.
Climate normals: NOAA 1991-2020 monthlies, ALPENA WWTP station (10 mi away).
Land & collecting status
Generally open to casual rockhounding
Most public-tagged spots sit on BLM, U.S. Forest Service, or other federal land where reasonable hand collecting of common rocks and minerals is allowed. Confirm posted rules and active mining claims before you dig.
Public-land rules vary by agency, season, and field office. The RockHoundR app pulls live BLM, USFS, NPS, and tribal overlays so you can see exactly which agency manages the ground at this spot.
Sources & verification
Spot details combine the public RockHoundR location dataset, normalized mineral labels, agency land-status checks in the app, and community submissions. Coordinates are approximate until verified in the field.
State guidance last verified:
- Michigan DNR — Rockhounding rules
- Michigan Geological Survey
- Isle Royale National Park — Rules
- Community submissions reviewed against published agency rules
Found at Rockport Recreation Area
Each chip opens all spots that produce that material; the encyclopedia link opens the full ID and field guide.
- Petoskey Stones
- Fossilized Coral
- Brachiopods
- Crinoid Stems
- PyriteEncyclopedia →
- Petoskey Stone
- Brachiopod
- Horn CoralEncyclopedia →
- Favosites
- Cladopora
- Bryozoan
- Stromatoporoid
- Gastropod
- Trilobite
- FossilsEncyclopedia →
Nearby rockhounding spots
Other rockhounding spots within driving distance of Rockport Recreation Area.
- Besser Natural AreaPresque Isle County, Michigan · 3 mi away
- Presque Isle ShorelineTop pick in MichiganPresque Isle County, Michigan · 13 mi awayAgate, Chalcedony Geode, Sandstone With Calcite Veins
- Partridge PointAlpena County, Michigan · 13 mi awayCrinoid, Brachiopod, Horn Coral
- Thompson's Harbor State ParkPresque Isle County, Michigan · 15 mi awayGranite, Gneiss, Quartz
- Negwegon State ParkAlcona County, Michigan · 24 mi awayPuddingstone, Petoskey Stone, Granite
- Seagull Point ParkPresque Isle County, Michigan · 27 mi away
- Hoeft State ParkPresque Isle County, Michigan · 30 mi awayPuddingstone, Granite, Quartz
- Sturgeon Point LighthouseAlcona County, Michigan · 34 mi awayGranite, Chert, Fossils
