The mighty Columbia River is the largest in the Pacific Northwest and usually referred to as one of the great waterways of North America. Itâ€™s the only river that has managed to saw its way through the Cascade Mountains and the result of such endurance is the magnificent Columbia River Gorge â€“ 60 miles of cliffs rising thousands of feet out of the river. Because of the underlying pitch of the bedrock, the northern side of the gorge has produced more landslides than waterfalls (see The Gifford Pinchot) but the Oregon side of the river has remained steadfast over the centuries. This is the smallest of the regions drawn up on this website â€“ stretching from the Willamette River in Portland to Highway 97 in The Dalles and south to the edge of the Sandy River watershed.
The Columbia River Gorge is well known for its waterfalls, some of which are among the most visited attractions in Oregon thanks to the close proximity to the Portland metro area. Many of the larger falls, such as Multnomah and Horsetail Falls, were likely discovered by the Lewis and Clark expeditions and they floated down the river, yet even with nearly 3 million people living less than an hour away, there are still waterfalls in the area that may have never been seen by man â€“ a testament to both the rugged geology of the area and the dedication to preserving the Gorge that has prevailed against decades of increasing population growth.