A lifetime can be spent experiencing diverse hikes, walks that abound in less populated regions of Oregon. The Northeastern edge of Oregon claims the state's highest mountain range, the Eagle Cap Mountains with numerous hikes to alpine lakes, views, wildflowers, Wallowa Lake (flanked by perfectly formed steep glacial moraines), and a (fee) tram at the south end of the lake up to Mt. Howard, with a variety of walks/hikes, restaurant and views. Numerous on-line and dedicated hiking guidebooks (see more information) provide comprehensive and detailed information.
Resources
National Historic Oregon Trail Interpretive Center - Baker City
1-3.5 miles of trail walks
Blue Mountain Land Trust - Umatilla County
Organizes walks, history lectures, volunteer trail maintenance
100 Hikes in Eastern Oregon - Eastern Oregon
Oregon based author and lifelong hiker William Sullivan's comprehensive hiking books