Sno-Park: Marble Mountain

Area Status: Open
Shelter with snow

Marble Mountain Sno-Park is the starting point for the Worm Flows Climbing Route for Mount St Helens Summit. This is the primary climbing route used during the winter. Marble Mountain Sno-Park offers a trail system that includes 25 miles (snowmobile), and 78.4 kilometers ungroomed (ski).

This area is shared with motorized and non-motorized recreationists. Marble Mountain Sno-Park is not a location for recreational sledding

Marble Mountain Ski Trail Map (.pdf)

Check Washington State Sno-Parks for current grooming conditions.

Climbing Related Information: 

⚠️ Important Alert: A dangerous cornice, an overhanging mass of snow formed by wind, grows through the winter on the leeward side of the wind exposed edge of the summit and crater. As it grows, the cornice can hang quite a distance over the edge, making it fragile and extremely dangerous to walk upon to get a view into the crater. Stay back at least 30 ft (9 m) from the visible edge. There may not be any flagging stakes or markers indicating the danger zone, so use extreme caution. The high summit drift may prevent you from having any view over the rim to the North. Always check current conditions before your climb.      

Click here to read the most current climbing conditions from Mount St. Helens Institute.

At a Glance

Current Conditions: 06/17/2024: ALERT! With Climber's Bivouac now officially open for the season, the process has begun to close Marble Mountain Sno*Park. All climbers must travel to Climbers Bivouac on Forest Road 830 to summit Mount St. Helens to avoid getting locked in to Marble Mountain Sno*Park. The road up to the park and beyond is cleared and snow free. Contact the Mount St. Helens National Volcanic Monument for more information at 360-449-7800.
Fees: Washington State Sno-Park Permit required Dec. 1 to March 31. 
Permit Info:
  • Mount St. Helens Climbing Permit required for each person, for each day, year-round, traveling above 4800 feet on the slopes of Mount St. Helens:  
    • April 1 through Oct. 31: Permits purchased in advance at on a rolling basis. 
    • Nov. 1 to March 31: Permits available at Marble Mountain Trailhead and are free.
  • Washington State Sno-Park Permit required Dec 1 to March 31.  Purchase online or at local vendors. One per vehicle. Not available on-site.
Usage: Heavy
Busiest Season: Winter
  • Snowmobiles are prohibited in the the Non-motorized corridor between Monitor Ridge and the Worm Flows climbing routes.
  • The restricted research area north of the volcano is closed to snowmobiles and to off-trail ski and snowshoe travel.
Closest Towns: Cougar, WA
Water: No
Restroom: Vault Toilets
Information Center:

General Information


From Cougar, WA drive east on Lewis River Road, which turns into Forest Road 90. Continue on Forest Road 90 until the intersection with Forest Road 83. Turn left on Forest Road 83 and continue approximately 6 miles to the Marble Mountain Sno-Park. During the winter and early spring  Forest Road 83 is gated at the Sno-Park.

General Notes:

Marble Mountain Non-motorized Winter Trails Map (.pdf)

Marble Mountain Non Motorized Snow Trails Vicinity Map

Recreation Map

Map showing recreational areas. Map Information


Mountain Climbing

Marble Mountain Sno-Park is the starting point for the Worm Flows Climbing Route. This is the primary climbing route used during the winter.

XC Skiing/Snowshoeing


Related Information

Recreation Areas

Recreation Activities


  Latitude : 

  Longitude : 

  Elevation : 
2,800 ft.