REI (for the record, Recreational Equipment, Inc., but nobody calls it that) is Seattle's sports-equipment mecca. The enormous flagship store has an incredible selection of outdoor gear and its own 65-foot climbing wall. The staff is extremely knowledgeable and there always seems to be enough help on hand even when the store is busy. You can try things out on the mountain-bike test trail or in the simulated rain booth. REI also rents gear such as tents, sleeping bags, and backpacks in case you don't want to lug all your camping stuff across the country.
Visit the Travel Talk forums for help on planning your trip >>