USFS · Montana

Helena-Lewis and Clark National Forest

Helena-Lewis and Clark National Forest is located in west-central Montana, United States. Spanning 2.8-million acres. The region was inhabited by various cultures of Native Americans for a period of at least 8,000–10,000 years. When the Lewis and Clark Expedition came to this area, different areas of the large forest territory were used by members of the Blackfeet, Sioux, Cheyenne, Flathead and Crow nations for hunting and as an area for their seasonal winter camps. The forests provided shelter from the winter.

From Wikipedia, licensed CC BY-SA 4.0.

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DesignationNational Forest
Managed byU.S. Forest Service
StateMontana
Size3.2 million acres (Forest Service administrative boundary (gis_acres))
Forest Service code0115, region 01
Center point46.8486, -110.6676
Night skyAbout as dark as the ground gets (Black Marble reading 10)

Boundary map

10 outlines

Boundary, simplified to about 0.005 degrees Federal campground

The outline is the agency boundary simplified for display, so small parcels and inholdings may not show. The agency page has the authoritative map.

Weather by month

NOAA climate normals →
Weather by month near Helena-Lewis and Clark National Forest20°30°40°50°60°70°JanFebMarAprMayJunJulAugSepOctNovDecJanuary: 26.6°F averageFebruary: 27.7°F averageMarch: 34.1°F averageApril: 40.9°F averageMay: 49.0°F averageJune: 56.6°F averageJuly: 64.1°F averageAugust: 64.1°F averageSeptember: 55.9°F averageOctober: 44.8°F averageNovember: 33.8°F averageDecember: 26.4°F averageTemp °F
The line is the average temperature at Neihart 8 NNW, 14 miles from the center point at 5,230 feet, station USC00246008 in the NOAA monthly climate normals for 1991 to 2020. The station sits about 2,500 feet lower than the center point, so temperatures on the ground run cooler.

Large units span more than one climate. The station stands in for the center point, and the outer parts of the boundary can be warmer or colder.

Where to camp

Campsite Atlas →

52 federal campgrounds sit inside the boundary and 26 more are within ten miles of it. Nearest first. Distances are from the campground point to the boundary edge, from the Campsite Atlas index.

Show 4 more

66 more within ten miles are not listed here.

The Forest Service trail layer records 744 named trails in this forest, 2,931 miles in all. The 10 longest are listed here.

TrailMiles
Continental Divide116.3
Snowmobile Loop J32.6
Two Med-Heart Butte27.1
South Fork Sun25.3
Tenderfoot24
North Fk Sun22.5
Crow Creek22
Dearborn River20.6
Moose Creek20.4
Cabin Creek19.1

Lengths and allowed uses come from the Forest Service trail layer by way of Trailhead Atlas, refreshed September 18, 2026. Trails in plain text have no page there yet.

All 744 trails in Helena-Lewis and Clark National Forest on Trailhead Atlas ↗

Explore

Nearby on the other atlases

National Register listings within 15 miles · 157 in all · Register Atlas

Landmarks are listed first, then by distance from the boundary.

Reference

Questions people ask

How big is Helena-Lewis and Clark National Forest?

3.2 million acres.

Source: Forest Service boundary data

Who manages Helena-Lewis and Clark National Forest?

The U.S. Forest Service.

Source: U.S. Forest Service

What state is Helena-Lewis and Clark National Forest in?

Montana.

Source: How states are assigned

Can I camp at Helena-Lewis and Clark National Forest?

52 federal campgrounds sit inside the boundary, including Aspen Campground, Aspen Grove Campground and Bar Gulch Cabin. 78 in all are within ten miles. Dispersed camping is allowed on most national forest land outside developed sites; check the forest page for closures.

Source: Where to camp

How do I get to Helena-Lewis and Clark National Forest?

A point inside the boundary is at 46.849, -110.668. Grant-Kohrs Ranch National Historic Site is 10 miles away. The official page carries directions and the office address.

Source: U.S. Forest Service

How dark is the night sky at Helena-Lewis and Clark National Forest?

NASA’s Black Marble night-lights image reads 10 on a 0 to 255 scale at the center point, about as dark as the ground gets.

Source: NASA Black Marble

Which national parks are near Helena-Lewis and Clark National Forest?

Grant-Kohrs Ranch National Historic Site (10 mi). Park Atlas has fees, hours and alerts for each.

Source: Nearby on the other atlases

Are there historic places near Helena-Lewis and Clark National Forest?

157 National Register listings within 15 miles, including Russell, Charles M., House and Studio and Two Medicine General Store.

Source: Register Atlas

Sources

  • Boundary, name, acreage and code: the Forest Service Enterprise Data Warehouse.
  • States: computed by intersecting the boundary with Census state polygons; a state is listed when it holds at least one percent of the area.
  • Description: Helena-Lewis and Clark National Forest on Wikipedia, CC BY-SA 4.0. The article was accepted because its title contains this unit’s name.
  • Campgrounds: the Campsite Atlas index of federal campgrounds, matched to this boundary at build time.
  • Trailheads and sites: the Forest Service Recreation Opportunities layer, matched by forest code.
  • Trails: the Trailhead Atlas open-data file of Forest Service trails, matched by forest code.
  • Night sky: NASA Black Marble (VIIRS, 2016 composite) sampled at zoom 6 around the center point.
  • Weather, alerts, air quality, river flow and earthquakes load live in your browser from NWS, AirNow, USGS and iNaturalist when you open the page.