Lake Wilderness Arboretum is .8 mi. s. of SR 169 via Witte Rd. S.E., then e. to 22520 S.E. 248th St. Specialty gardens include the Legacy Garden, which features rare and unusual plants, and the Hydrangea Garden, which is in bloom during the summer. Paths wind through the Smith-Mossman Garden, where peak bloom for the large collection of deciduous Western azaleas is late May to early June. The arboretum's rhododendrons bloom in May and June.
Other areas feature perennials, day lilies, Japanese maples and plants that thrive in shade, rocky areas and at high altitudes. For hikers, a Northwest second-growth forest ecosystem is laced with marked trails.
Guided tours are available. Picnicking is permitted.