This parking lot for Multnomah Falls exits off the the left of Interstate 84, the lot looks big but during the summer and Beautiful weather in spring and fall it's full easily. There are gates that close when lot is at capacity.
On my recent visit there was plenty of parking when I arrived but when I left it was half full and tour busses had arrived. This is the preferred parking area when coming to Multnomah Falls for a hike, meal at the lodge or just to snap a photo of one of Oregon's most popular tourist hiking locations.
During the Summer there is timed entry to the parking lot and the main side roads to the Columbia River Gorge.