"The Trillium Lake Trail circles the lake and affords a visit, via a series of boardwalks, to its less-trafficked west shore, where a variety of wetland wildflowers can be observed in the summer," writes OregonHikers.org. The boardwalk and trail loop is almost entirely flat, making it fun for the whole family. The trail runs beneath the bows of cedar, spruce, and silver firs, and in other places, it winds through willow thickets and through fields of subalpine wildflowers.

Note that Trillium Lake is one of the few concessionaire sites in the Mount Hood National Forest, making the Northwest Forest Pass invalid here. You'll have to pay a $5 fee to access the lake.