Earthquake Lake

A severe earthquake caused a massive landslide on August 17, 1959 at 11:37 p.m. Several faults in the Madison River area moved at the same time causing an earthquake that triggered a massive landslide.

The slide moved at 100 mph and happened in less than one minute. Over 80 million tons of rock crashed into the narrow canyon, burying an open meadow where some campers had stopped for the night.

The landslide completely blocked the Madison River and caused it to form Earthquake Lake. The force of the slide displaced both the air in the canyon and water of the Madison River. It created high velocity winds and a wall of water that swept through the area, just downstream from the slide, killing five people in its path.

Earthquake at Hebgen Lake

The Hebgen Lake Earthquake measured 7.5 on the Richter scale. At least three blocks of the earths crust suddenly dropped as two faults moved simultaneously the Red Canyon fault and the Hebgen Lake fault.

The north shore of Hebgen Lake dropped 19 feet and cabins fell into the water. Hebgen Lake sloshed back and forth. Huge waves called seiches crested over Hebgen Dam. This earth filled dam cracked in at least four places, but held. Three sections of Highway 287 fell into the lake. Hundreds of campers were trapped.

28 people lost their lives as a result of the earthquake. Their names appear on a bronze plaque on one of the massive dolomite boulders carried across the canyon by the slide. The dolomite boulder serves as a memorial.

Madison River Canyon Earthquake Area

This immense earthquakes impact shocked and chilled the world. Families gradually rebuilt their lives, structures and roads were reconstructed.

In 1960, a 38,000 acre area in the canyon was designated as the Madison River Canyon Earthquake Area. This portion of the Gallatin National Forest is of great scientific and general interest.

As you travel through this area, the effects of the ever-changing earth can be seen all around you.

The Visitor Center is located on Highway 287, 17 miles west of Highway 191, and 25 miles to the town of West Yellowstone, Montana.

This facility is accessible to people with disabilities.

Open: Memorial Day - late September, 7 days a week, 8:30 - 6:00 p.m. Telephone: 646-7369 (V/TDD)

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Map Guide

1. A Spillway was cut across the slide by the U.S. Army Corps of Engineers. On September 10, 1959 water passed through the 250 ft. wide and 14 ft. deep channel. On October 17, 1959 the channel was deepened another 50 ft.

2. Visitor Center and Slide - Come and view the slide from the observation room. Listen to the interpreters story. Walk the trail to the Memorial Boulder and overlook.

3. Rock Creek Turnout - A Forest Service campground lies under 100 feet of water just off this point. Some campers escaped and others perished from the rising waters.

4. Earthquake Lake - The slide dammed the Madison River to form Earthquake Lake, which filled in three weeks and created a new body of water 190 ft. deep and 6 miles long.

5. Boat Launch - This portion of the old highway continues to serve the public. The old highway lies beneath the waters of Earthquake Lake.

6. Refuge Point - This ridge provided a place of protection during the night of August 17 for many survivors of the earthquake. The next morning Forest Service smoke jumpers parachuted to this point and set up rescue operations. Later that day helicopters evacuated the survivors.

7. Ghost Village - These deserted cabins were displaced here from the waters of Earthquake Lake.

8. Cabin Creek Scarp - At this site a 21 foot fault scarp severed the old campground.

9. Hebgen Dam - The earth fill dam held, although it suffered damage from tremors and huge earthquake caused waves called seiches.

10. Building Destruction - A short walk will take you through this area. You can see the old resort cabins that are submerged in Hebgen Lake.

11. Road Destruction - One of the three places where the road collapsed into Hebgen Lake. Look along the old roadbed to see where the land shifted during the earthquake.

12. Red Canyon - You can view the fault scarp that extends 14 miles in this area. A fault scarp is a cliff created by movement along a fault.

13. Duck Creek Y - This is where the epicenter of the earthquake occurred.

Reprinted from U.S. Forest Service brochure.