Fremont County: Fossil Hunting in Fremont County, Iowa

Quick details

Access

Public area

County

Fremont County

State

Iowa

Nearest road

200 Street

Postcode

51652

Coordinates

40.75107, -95.67717

Geology at Fremont County

This spot sits on ground mapped as Waubonsee Group that formed roughly 305 to 300 million years ago. Fossils here are typically found in fresh exposures, where erosion keeps bringing new material to the surface.

Mapped unit

Waubonsee Group

Age

305–300 Ma (Pennsylvanian)

Elevation

1,020 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 Fremont County

Best months: March to November. Typical highs run 86°F in midsummer and 33°F in midwinter, with winter lows near 14°F.

Climate normals: NOAA 1991-2020 monthlies, SIDNEY 1SSE station (2 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.

Sources: RockHoundR public spot dataset, app land overlays, and local agency review before each trip.

Found at Fremont County

Each chip opens all spots that produce that material; the encyclopedia link opens the full ID and field guide.

• Fossilized Coral
• Stromatoporioids