Mt. St Helens for day trip in toad. Leave MH closer to I-5. There is two visitor centers. Best one is Coldwater Ridge.
East of Portland on US 26 is Government Camp and access to Timberline lodge on Mt. Hood. Leave MH in Portland or Rhododendron and take toad.
Too bad you do not have more time. The north Cascades Loop via WA SR20 and retuning west on US 2 is very scenic. Winthrop, WA is a western motif town and Leavenworth, WA is a Bavarian motif.
Bud
USAF Retired
Pace Arrow
2003 Chev Ice Road Tracker