Folks who are interested in nudism, but perhaps are not ready to commit to visiting a "Nudist Club" should consider visiting one of the area's several hot springs. Hot springing is an excellent introduction to social nudity. Most (non-commercialized) hot springs have a "clothing optional" policy -- or, as Evie Litton writes in Hiking Hot Springs in the Pacific Northwest you can "wear what you normally bathe in."
Goldmyer Hot Springs, located 25 east of North Bend, is far and away the best in the region. While there is a modest entry fee ($15), it is immaculately kept, and an on-site caretaker ensures there are no drugs, alcohol, or general rowdiness. The spring is in an "enhanced" natural state, emanating from a cave, and filling several small pools of varying temperature. A 20 person per day limit is strictly enforced, and reservations are highly recommended. (You WILL be turned away when the limit has been reached.)
Scenic Hot Springs, while a shadow of its former self, is still a fun place to visit. It also requires a reservation and an entry fee ($5/weekdays, $10/weekends), and is much easier to reach than Goldmyer. Two tarp-lined tubs provide a "warm" and "hot" option to soak in while looking out across the valley.
Baker Hot Springs is a truly "natural" springs. It is located on Forest Service land about an hour outside of Mt. Vernon. There are no facilities whatsoever, but it is free and no reservations are required. It can be crowded on weekends, so those wishing to ease into the "clothing optional" world would be advised to visit midweek. While it's a long drive from Seattle, it's also an excuse to visit the fabulously eclectic Birdsview Brewing Company in Concrete, WA.
For the hardy, Olympic Hot Springs, located outside of Port Angeles, is a beautiful set of springs in the foothills of the Olympic Mountains. Due to the Elwha Restoration project, access is limited to a fairly brutal hike over Aurora Ridge or Appleton Pass. However, what is lost in ease of access is made up for in solitude.
As with all hot springs, winter is the best time to visit. The journey may be more arduous, but the reward is much greater.