Yellow Breeches Creek: Potomac Marble Rockhounding in Cumberland County, Pennsylvania

Updated June 2026

Yellow Breeches Creek is a mapped rockhounding spot in Cumberland County, Pennsylvania. Reported finds include potomac marble. Below: coordinates, access notes, nearby spots, and trip-planning links.

Quick details

Access: Public area
County: Cumberland County
State: Pennsylvania
Nearest road: Main Street
Postcode: 17055
Coordinates: 40.17057, -76.91065

Geology at Yellow Breeches Creek

This spot sits on Gettysburg Formation, mapped as siltstone mudstone and shale that formed roughly 250 to 200 million years ago. Sedimentary rock like this erodes unevenly, so the most productive collecting is typically along fresh cuts, badland slopes, and active drainages.

Mapped unit: Gettysburg Formation
Age: 250–200 Ma (Triassic)
Rock types: siltstone mudstone and shale
Elevation: 370 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 Yellow Breeches Creek

Best months: March to November. Typical highs run 87°F in midsummer and 40°F in midwinter, with winter lows near 25°F.

Climate normals: NOAA 1991-2020 monthlies, HARRISBURG CAPITAL CITY AP station (4 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 Yellow Breeches Creek

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

Potomac Marble

Nearby rockhounding spots

Other rockhounding spots within driving distance of Yellow Breeches Creek.

Across the state line from Yellow Breeches Creek

Yellow Breeches Creek is close enough to the Pennsylvania border that the next-closest rockhounding spots are in a neighboring state. Worth knowing if you are already on the road.

Yellow Breeches Creek FAQ

Where is Yellow Breeches Creek?+

Yellow Breeches Creek is in Cumberland County, Pennsylvania, at 40.17057, -76.91065. Nearest road: Main Street.

What rocks and minerals can you find at Yellow Breeches Creek?+

Yellow Breeches Creek is reported to produce Potomac Marble.

Is collecting allowed at Yellow Breeches Creek?+

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. Always confirm current rules with the managing agency before a trip.

What tools should I bring to Yellow Breeches Creek?+

A rock hammer, sturdy gloves, safety glasses, and a collecting bag cover the basics here. Add a spray bottle: wet rock shows color and pattern that dry rock hides.

When is the best time to visit Yellow Breeches Creek?+

The most comfortable months at Yellow Breeches Creek are March to November.

How do I get to Yellow Breeches Creek?+

Open the directions link to navigate to 40.17057, -76.91065 in Google Maps. The nearest road is Main Street.

More rockhounding in Pennsylvania

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Open Yellow Breeches Creek on the map

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