The Lewis and Clark expedition, and the many settlers and traders that followed, met their last obstacle to their journey at the Cascades Rapids in the Columbia River Gorge, a feature on the river now submerged beneath the Bonneville Reservoir. Before long, the great white-capped mountains that loomed above the rapids were called the mountains by the cascades and later simply as the Cascades. The earliest attested use of the name Cascade Range is in the writings of botanist David Douglas.