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Mammoth Lake

Mount Pleasant, Pennsylvania — Westmoreland County.

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27Surface acres
1Public access sites
1.1 miShoreline trails

Surface area: The USGS National Hydrography Dataset outline (NHD Permanent ID 69927123).

Location & fast facts

Where Mammoth Lake is in Pennsylvania

The red circle marks Mammoth Lake.

Fast facts

About Mammoth Lake

  • County: Westmoreland
  • Town: Mount Pleasant
  • Mapped as: Lake or pond (USGS National Hydrography Dataset)
  • Distance: about 136 mi from Harrisburg and 32 mi from Pittsburgh, straight-line (not driving distance)

Towns and counties: U.S. Census Bureau boundaries overlaid on the USGS lake outline.

Fishing in Pennsylvania

Official PFBC pages. Rules and fees change; check before you go.

Good for & watch for

Good for

  • Paddling. 1 public access site, no trailer ramp listed
  • Fishing. Largemouth bass, Black crappie, White crappie and Bluegill
  • Walking. 1.1 mi of trail near the shore (trails)
  • Camping. 6 campgrounds within 15 mi (list)

Watch for

  • Cold water. Water stays cold well into late spring and turns cold again in fall. Wear a life jacket when paddling in the shoulder seasons.

Built only from the data on this page: official access lists, OpenStreetMap beaches and trails, campground listings, state and USGS invasive-species records. We don't rate crowds or water quality.

Official fishing data (PA Fish and Boat Commission)

27Acres (state figure)

Fish species listed by PFBC biologists as warmwater/coolwater fishing opportunities: Black crappie, Bluegill, Largemouth bass, White crappie, Yellow perch.

Trout: PFBC stocked trout water

Source: Pennsylvania Fish and Boat Commission (PFBC) warmwater/coolwater fisheries lakes and stocked trout waterbodies (via PASDA), record for Mammoth Lake, Westmoreland County. See PFBC fishing for regulations and stocking schedules. Acreage here can differ slightly from our mapped outline.

Lake map

Mammoth Lake shoreline, boat launches & beaches

Mammoth Dam (Cartop / walk-in)10.1 mileN

Numbers on the map match the list at rightbelow.

Cartop / walk-inShoreline trail
  1. 1Mammoth Dam
    Cartop / walk-in · Mount Pleasant

Shoreline: USGS National Hydrography Dataset (NHD Waterbody, Permanent ID 69927123), public domain. State outline: U.S. Census Bureau TIGERweb. Points: PFBC fishing and boating access points. Dashed trails: © OpenStreetMap contributors (ODbL). Interactive map: Leaflet with © OpenStreetMap contributors. Not for navigation.

Shoreline trails

1.1 miTrail within 70 m of shore
About 100%Of the shoreline
YesLoops the whole lake

OpenStreetMap shows about 1.1 mi of public hiking and walking trail within about 70 m (230 ft) of the Mammoth Lake shoreline. Together the trails go all or nearly all the way around Mammoth Lake, staying close to the water.

Trails along the shore

Getting to the trails

No trailhead is mapped for these trails. The closest public access site is Mammoth Dam, right on a shoreline trail (PA Fish & Boat Commission access data).

The dashed brown line on the lake map shows these trails. We include paths, footways and marked trails that OpenStreetMap doesn't mark as private, and leave out roads, sidewalks and snowmobile corridors. Mapped trails can still cross private land or close for the season, and not every trail is mapped, so follow posted signs.

Trails: © OpenStreetMap contributors, available under the Open Database License (ODbL). Map data as of Oct 9, 2026. Trail lengths count only the parts within about 70 m of the USGS NHD lake outline.

Campgrounds near Mammoth Lake

We found 6 campgrounds and RV parks within 15 miles of Mammoth Lake. Distances are straight-line from the nearest point on the shoreline, so driving distance is longer.

All campgrounds & RV parks in Pennsylvania

Green tent icons on the lake map mark campgrounds near the shore, and the interactive map shows the closest 12. Amenities are listed only where a source records them; call or check the campground's website before you go, since seasons and rates change every year.

Campground data: OpenStreetMap contributors (ODbL). Pulled Oct 12, 2026.

Conditions right now

Air temperature & conditions (nearest NWS station)Loading…
Fetching the latest National Weather Service observation…

Live from the National Weather Service API for the lake's coordinates (40.2135, -79.4566). The nearest station may be several miles away. NWS forecast for Mammoth Lake. No live water-temperature sensor is shown because we haven't found a public one for this lake.

Sun, moon & best fishing times

Sun & moon at Mammoth Lake

Best fishing times

Major periodMinor periodDaylight

    Based on solunar theory, an estimate. Major periods (about 2 hours) center on when the moon is directly overhead or underfoot; minor periods (about 1 hour) center on moonrise and moonset. The 0–100 activity score rises during those periods and gets a boost near sunrise and sunset and around the new and full moon. Weather, water temperature and pressure often matter more. Sun and moon times are calculated in your browser from the lake's coordinates with standard astronomy formulas, shown in ET (America/New_York), and accurate to within a few minutes.

    Boat launches & access sites

    1 public access site listed.

    SiteTownOwnerTypeParkingFeeUsesMap
    Mammoth DamMount PleasantUnknownCarry-in (hand launch)—No feeBoating40.2147, -79.4566

    PFBC fishing and boating access points

    Fees, hours and rules change; confirm with the site owner before you go.

    Contact & official info

    Questions about Mammoth Lake

    How big is Mammoth Lake?

    Mammoth Lake covers about 27 acres in Mount Pleasant, Pennsylvania (Westmoreland County).

    What fish are in Mammoth Lake?

    Pennsylvania Fish and Boat Commission lists Largemouth bass, Black crappie, White crappie, Bluegill and Yellow perch.

    Is there a public boat launch on Mammoth Lake?

    No trailer ramp is listed, but there is 1 public access site for car-top boats or shore access.

    Are there campgrounds near Mammoth Lake?

    Yes. We list 6 campgrounds and RV parks within 15 miles.

    What towns are on Mammoth Lake?

    Mammoth Lake touches Mount Pleasant in Westmoreland County, Pennsylvania.

    Share a tip or fishing report

    Know Mammoth Lake? Tell us about the launch, parking, where they're biting or anything a first-time visitor should know. Tips go privately to the LakeRipple editor; nothing is posted automatically. Helpful tips may be featured on this page (we'll use your first name only if you give one).

    Lakes & ponds nearby

    Straight-line distance between lake centers. All Pennsylvania lakes & ponds · All waters in Mount Pleasant