Sauvie Island

"Roughly the size of Manhattan, Sauvie Island sits 20 miles outside of Portland, flanked by the Columbia River, Willamette River, and Multnomah Channel. There’s plenty to do here on a day trip; depending on the season and the weather, you can hang at the river beaches, ride bikes, check out the wildlife (the northern half of the island, which is owned by the Oregon Department of Fish and Wildlife, is big for bird-watching), and/or pick berries or pumpkins at one of the local farms. (If you’re headed here with the family for a beach outing, just be aware that a part of one of the beaches, Collins, is clothing-optional.)"