This trail has the dubious distinction of not being inside Mount Rainier National Park at all. It's actually a section of the Pacific Crest Trail, slightly outside the eastern park boundary. That means you can bring dogs!

Start at Chinook Pass, and hike northeast along a level section of trail that hugs the steep side of the valley, parallel to but above the road. You often won't see the road, but you sure can hear it.

After a mile and a half the trail separates from the road (hurrah, no more traffic noise) and enters forest before passing Sheep Lake, where you are likely to see tents and encounter smelly PCT backpackers. Being outside the National Park, camping here does not require permits and there are no toilets or bear poles.

After Sheep Lake the trail heads more steeply uphill, trees dropping away as you approach the rocky and impressive high pass named Sourdough Gap. This is actually a double pass, linking three separate drainages within a quarter of a mile. First you leave the Rainier Fork American River drainage to gaze over the headwaters of Morse Creek, then continue a short distance straight ahead after the PCT veers off to the right, traverse a scree slope, leave the Morse Creek drainage for the Crystal Lakes one, and enter Rainier National Park.

If you're anything like me you'll have been missing the lack of Rainier summit views so far. Immediately ahead, as the trail loses altitude, you'll find some tasty views of Her Majesty. No dogs allowed on this last stretch, though. Thanks T for hanging onto ours at the park boundary while I sprinted ahead!

If you want to go further, continue on the Crystal Lakes and Sourdough Gap trail, which drops steeply from here down to WA 410. Would be neat to through-hike if you can arrange a car at both ends.