The Worm Flows route is the most direct route up to Mount St. Helens’ crater during the winter months, but it also remains a viable option during the summer season. This route allows climbers to practice basic mountaineering skills without having to navigate crevasses.
Proficiency in snow travel can be beneficial for climbing the mountain, especially during winter and early spring. However, as the season progresses and the snow melts away, the emphasis shifts to trekking skills. Regardless of the season, it’s crucial to know how to use your gear correctly—specifically, items like ice axes and crampons. An ice axe can serve as a supportive tool during the ascent and act as a brake when glissading down.
The increase in the number of climbers has made the route more discernible, making navigation less intimidating for newcomers. Starting from the Marble Mountain trailhead, you’ll enter a wooded area to commence the trail, marked by markers on the trees. Continue through the forest for roughly 2.3 miles (1.25 hours) and ascend about 1,000 feet vertically along a gradual incline.
Cross Swift Creek above Chocolate Falls—a great spot for a rest or camping—before moving into the alpine zone. Follow the ridges and slopes up to the crater rim, with the last 2.5 miles of the ascent being a constant uphill climb.
Most climbers stop at the rim, but the true summit involves a longer walk around the rim and an additional climb of around 200 feet. On a clear day, you’ll have breathtaking views of Spirit Lake and Mount Rainier to the north, while Mount Adams and Mount Hood are visible to the south and east throughout the climb.
At the rim, be cautious of snow cornices, or windblown snow lips, which can fall and break away under weight or in warmer weather—this is particularly important during the transition from winter to spring.
For the ski descent in winter, aim to avoid crossing over the uphill skin tracks and bootpack when possible, as it results in less choppy skiing. Uphill travelers have the right of way, so it’s crucial to steer clear of them. Only use the uphill track when visibility is low.
Aim for Chocolate Falls and steer clear of valleys that will lead you lower than the entrance to the narrow trail through the trees back to the parking lot. This guidance applies to both winter and summer descents, though the summer trek may be more forgiving. Always communicate with foot traffic as you approach to maintain your momentum on the gradual decline, regardless of the season.