The classic ascent of the 14,005ft Mount of the Holy Cross, this 10.8-mile round-trip hike is best done as an overnight if you plan on making the summit, but you can also simply hike up to Half Moon Pass (1.5 miles) for a short day hike (you won't see the cross from here, though). Over a dozen campsites are located 2.8 miles in.
Note that this mountain involves class 2 scrambling. It's for experienced hikers only and a compass and topo map are highly recommended – coming down can be tricky. Access is the same as for Notch Mountain, but you begin at the Half Moon Trailhead.