The Big Beaver Trail leads northwestward from Ross Lake 14 miles along Big Beaver Creek. The trail gains approximately 2,060 feet as it climbs through the drainage to Beaver Pass. It leads through a considerable amount of marsh, which makes for good insect habitat. Check with rangers about trail conditions and possible alternatives to this long and vista-less trail.

Begin this trail at the Ross Dam Trailhead near mile marker 134 on Highway 20. Cross the dam and hike northward along the western shore of the lake. The elevation along this stretch is low, near 1,500 feet, so it can be very hot during the summer months.

Follow the Ross Dam Trail past Ross Lake Resort and Green Point Camp. Through this area views of the lake abound. A short distance past the boaters camp the trail leaves the lakeshore, begins to ascend then enters a forested area. Within a mile of leaving the lakeshore the trail reaches a junction. The trail leading westward from this junction is the Sourdough Mountain Trail.

Follow the right fork of the trail, it contours the lakeshore almost three more miles to the mouth of Big Beaver Creek. In this three mile stretch the trail remains level before descending 325 feet to Big Beaver Camp at the mouth of the creek. The trail crosses three streams and leads northwestward as the shoreline leads to Big Beaver Creek. Immediately before reaching the creek the trail passes boaters camp Pumpkin Mountain. It is approximately six miles from the Ross Dam to the mouth of Beaver Creek.

Between the Pumpkin Mountain and Big Beaver Camps the trail crosses Big Beaver Creek, on a steel foot/stock bridge, and turns westward up the drainage. The first quarter mile of Big Beaver Creek is closed to fishing to allow for the spawning of rainbow trout. Within a mile of the lake the trail makes a wide northward curve around a marshy area created by beaver. Some of the beaver work along this stream is estimated to be nearly 150 years old. The marshland throughout this drainage is protected as a Research Natural Area designated in 1991.

Three miles upstream from Ross Lake is a grove of ancient red cedars. This grouping of trees is considered one of the largest stands of red cedars in the world. The trail leads through the grove as it nears 39 Mile Camp. Also in close proximity to this camp is an active beaver dam and lodge where hikers may view a variety of plants and animals. The camp lies at the mouth of 39 Mile Creek.

Leading northward the trail continues at a level grade for the next two miles as it reaches the mouth of McMillan Creek. Hikers will notice the wide view down this drainage as they pass. The creek, and some interesting formations within its headwaters, were named after a homesteading family who lived within the Big Beaver drainage.

Beyond McMillan Creek the trail begins to ascend and turns northward. The surrounding peaks come into view as the trail climbs to the head of Big Beaver Creek. The trail continues to follow the eastern shore of the creek as it crosses four tributaries draining from the western flanks of Mt. Prophet.

Four miles north of McMillan Creek the trail crosses the last of four streams draining into Big Beaver Creek and leaves the stream side. The trail scales the northeastern valley wall ascending 1,150 feet to Beaver Pass. On the pass you'll find a few campsites in a forested area. One site can accommodate stock animals.

The trail continues north of the pass on a mild then steep descent. After two miles, one with steep switchbacks, the Big Beaver Trail ends at a junction with the Little Beaver Trail along the Little Beaver Creek. From this junction it is less than one mile east to Stillwell Camp. It is approximately five miles west to Whatcom Pass.

Directions from Rainy Pass: Drive 24 miles west on Highway 20 to the Ross Dam Parking area near mile marker 134. Park in the lot on the northern side of the road.

Directions from Marblemount: Drive eastward on Highway 20 to mile marker 134. Park in the Ross Dam parking area on the northern side of the road.

Seasonal Information:
Normally Open: July through September (NOTE: The upper portion of the trail may be snow covered in Early Summer and Early Fall.) .