Washington State white water river rafting on the Wenatchee, Skykomish, Tieton, and Skagit rivers outside of Leavenworth and Seattle, Washington. Alpine Adventures has been running whitewater river rafting trips for 18 years. The closest whitewater rafting to Seattle is on the Skykomish River. Our most popular whitewater rafting fun in the sun is on the Wenatchee River in Leavenworth.