Over 900 species of trees, some indigenous to the Pacific Northwest and others imported from around the world, are found in the hills and meadows of this 175-acre arboretum at the south end of Washington Park. Trails wind through well-established stands of magnolias, maples, oaks, hawthorns, cherries, and the most extensive conifer collection in the U.S. There are views of Mount Rainier, Mount St. Helens, and Pittock Mansion along the way. The short Overlook Trail, just south of the Washington Park light rail station, leads to the Visitor Center (you can also drive there), where visitors will find maps and booklets for self-guided tree tours. Bristlecone Pine Trail off Fischer Lane is a 1-mile paved trail with disabled access parking.

The Vietnam Veterans of Oregon Memorial, dedicated in 1987, lies at the southwest corner of the arboretum. From a central, bowl-shaped area, an ascending walkway spirals up to six black granite markers inscribed with the names of those reported as dead or missing from 1959 to 1976. Short texts inscribed above the names provide a "living history" of Oregonians during the war years.