Maryhill State Park (509/773-5007) is five miles east of the Maryhill Museum and right along the Columbia River near the intersection of Highways 14 and 97. Maryhill State Park offers Columbia River waterfront access for boating, windsurfing, and fishing. A $7 fee grants you all-day access to one of two boat launches and a nearby dock. Once you dry off, you can also unwind taking a stroll and looking for waterfowl along 1.1 miles of trails here.
Maryhill State Park is open for day use 6:30 a.m.–dusk in summer and 8 a.m.–dusk the rest of the year. You can also camp here year-round, in 50 full-utility RV campsites ($24), 20 standard tent sites ($17), and showers. Make reservations ($7 extra) at 888/226-7688 or www.parks.wa.gov [1].
A Travel Information Center here has Columbia Gorge [2] and Washington state information seasonally.
You can also camp or park RVs along the river at Peach Beach Campark (509/773-4698).
Links:
[1] http://www.parks.wa.gov
[2] http://www.moon.com/destinations/washington/columbia-gorge-and-wine-country/the-columbia-gorge