The Little Volcanoes
Take advantage of Oregon geology and escape the urban clamor on one of Portland's scores of small cinder cones. Between about 2.7 million and 500,000 years ago, the Boring Lava Field produced basalt eruptions throughout the Portland vicinity. Many of the city's high points are Boring Lava vents, including the well-known Mount Tabor. Powell Butte, a 620-foot cinder cone in east Portland, features a nature park with nine miles of hiking trails. Be sure to check out the Mountain View Trail, which leads to an old, windswept orchard from which a grand prospect sweeps from Mount St. Helens southward all the way to the wild fang of Mount Jefferson.
The West Hills
The Tualatin Mountains (also known locally as the West Hills) comprise the western backdrop to downtown Portland. Actually an arm of the Coast Range, these low, heavily-forested ridges contain a nice blend of cultivation and wilderness, from the serene paths of the Japanese Garden to the shadowed refuges of Forest Park, one of the largest urban preserves in the country, which boasts over 70 miles of trails. One of the best ways to explore Forest Park and the Tualatin Mountains is via the 30-mile Wildwood Trail.
Watch for great blue herons, Portland's official bird, along any of the metro area's waterways---especially at places like Jackson Bottom Wildlife Refuge along the Tualatin River in Hillsboro, or Maddox Woods in West Linn and Oaks Bottom Wildlife Refuge near downtown Portland. These all lie near active heron rookeries.
Head south of Portland along the west banks of the Willamette to explore one of the metro area's larger wildlands, Tryon Creek State Park. Miles of hiking trails explore the steep ravines of the Tryon Creek drainage, blanketed in a pretty forest of Douglas-fir, big-leaf maple, red cedar, alder and a bristling understory of Indian plum, salal, Cascade mahonia and ferns. The park is particularly renowned for its spring display of big, flashy trillium.
Black Rock Plateau
The Nature Conservancy's oldest holding in Oregon is the 26-acre Camassia Natural Area, a striking patch of wildness in West Linn above Willamette Falls. This plateau was scoured some 15,000 years ago by the immense Missoula Floods, outwash from a breached Ice Age lake in present-day Montana that ravaged a vast portion of the Columbia Plateau and parts of the Willamette Valley. Hike the loop trail to explore conifer woods, small wetlands and a beautiful, boulder-studded white oak/Pacific madrone woodland, watching all the while for hummingbirds and nesting osprey.
Walk the high lava bluffs of Oregon City for the best view of Willamette Falls, a horseshoe-shaped basalt plunge of the Willamette River that ranks as the 18th-most voluminous cascade in the world. The cliff-side path at McLoughlin Promenade Park above downtown affords a panoramic view, which includes not only the Falls but also the West Linn hills and the Camassia plateau. The deep holes below the Falls are famous for their congregations of fish, from migrating salmon and steelhead to enormous white sturgeon (which can be seen jumping sometimes). California sea lions occasionally trek upstream from the Pacific to enjoy the feast here.