The Amtrak Cascades connects Portland, OR and Vancouver, BC daily.
Trip time: ~4 hrs 10 min
Fare (2023 approx.): $59.50 one-way / $119 round-trip (varies by class, booking time)
Scenic Pacific Northwest views: Columbia River Gorge, Mount St. Helens, Puget Sound, coastal mountains. Border clearance at Pacific Central Station (Vancouver). Passport/visa required.