Located in the city of Newcastle, the May Creek Trail follows the historic route of the Seattle-Walla Walla Railroad, which transported coal from the mines once operating in present-day Cougar Mountain Park. Now the old railroad (which never got near Walla Walla) has become a pleasant woodland trail that follows the edge of the forested gorge of May Creek.
The trail drops down some steps into the deep forested valley of May Creek. After a short traverse, the trail reaches the old railroad grade, which crossed the valley on a long-gone trestle bridge.
The May Creek Trail continues heading east along the edge of the valley, the soft rush of mighty May Creek coming up from below. May Creek is the third largest tributary of Lake Washington, and can have an impressive flow of water in winter. After 0.8 miles from its start, the trail arrives at Sylvan Creek's small ravine, which it crosses on a fill. Just beyond the creek is a house with a horse paddock; the trail passes to the right of the house, then reenters forest.
Still following the old railroad grade, the trail reaches a grassy strip, the Waterline Trail, about a half mile from Sylvan Creek. Just before the Waterline Trail, look for a trail branching off right toward May Creek. This is the continuation of the May Creek Trail. The path descends on nice switchbacks down to the lushly vegetated floor of May Creek's valley.
Part way down is the shell of an rusty old van (1950s vintage perhaps) that has been turned into a display of sorts, complete with protective fence.
The trail comes quite close to the rushing waters of May Creek, a pleasant spot to rest for a bit, then after crossing a big, brand-new bridge over Lake Boren Creek, it gradually climbs to meet Coal Creek Parkway near the May Creek Road intersection.
Walking the whole length of the May Creek Trail and back covers about 3.5 miles. If you want more exercise, you can cross Coal Creek Parkway and head into "The Highlands" development, where there is a network of greenbelt trails (shown on the Cougar Mtn Green Trails map). Above The Highlands, you can continue hiking on the Terrace Trail and head into Cougar Mountain Park itself.