“Breathtaking views on this out and back trail.”
— Luke H
River/Creek · Views · Waterfall · Wildflowers
The hike up the Mill-Castle Trail to Storm Pass is one of the most scenic in Colorado. The landscape is unique, stunning, and sees relatively few visitors. However, the hike is not easy. While the trail itself is generally well maintained and gentle, it is long and with all the ups and downs, requires over 4,000 feet of elevation gain.
The first mile and a half is very easy and follows an old dirt road. From the trailhead, you get your first views of the incomparable rock walls and formations of Mill Creek Valley but the best views are when you enter the valley to cross over the creek at the 1.5-mile mark. Cross Mill Creek (which may be tricky at high water levels) and once on the other side you enter the aspen forest and shortly the wilderness boundary.
From this point, the hike rolls gently over aspen covered hills. Soon you’ll pass over a landslide/flood recovery area and pass through a cattle gate. Here, the trail begins to get rockier and you need to climb over some steep and narrow switchbacks. The trail starts to climb higher over Mill Creek with a few steeper rocky sections before you reach the waterfall, which you’ll see from a rocky viewpoint. The waterfall is roughly 4 miles from the trailhead.
From the bench, the trail levels out as you pass through pine forest and meet up again with Mill Creek. The trail is not signed but if you are looking for it, it is obvious—there is a large cairn a few feet up-trail. Once on the trail to Storm Pass, you need to pick your way along a faint trail through overgrown willows but before long you’ll enter the wide open Mill Creek Basin up to Storm Pass and get ready to enjoy the views!