Three views of Multnomah Falls through history. 1. Without bridge. The first view of Multnomah Falls, as it would have appeared from the time of the Missoula Floods 15,000 years ago, and what inspired Meriwether Lewis to note in his journal in 1806: "The most remarkable of these casscades falls about 300 feet perpendicularly over a solid rock into a narrow bottom of the river on the south side." Perhaps it was the low vantage point of the river from which Lewis spotted the falls, because he unde