Though the rugged geology is lacking in comparison to the Cascade Mountains in Washington and the number of Glaciers is exponentially fewer, the Oregon Cascades are thought to have just as many waterfalls as Washington does. The Northern half of the mountains, outlined in this region, is bound by the Willamette Valley on the west, Highway 97 and the Deschutes River on the east, the Sandy River basin on the north and the Willamette River basin on the south.
This region is punctuated by the tallest and most notable volcanoes of Oregon, Mounts Hood and Jefferson, the Three Sisters, Broken Top and Mount Bachelor, among others. The volcanoes supply a great deal of water to the rivers of the region, fed by their modest networks of glaciers. Unlike Washington, the volcanoes of Oregon do not possess a large number of waterfalls directly on their flanks due to substantial erosion and past eruptive history which didnâ€™t form bedrock nearly as solid. Instead most of the waterfalls in the region occur as a result of much older volcanism. Many waterfalls in this region occur where streams intersect abrupt basalt ledges or steps in valleys. The subsequent waterfalls are often much more scenic than in Washington, but on average arenâ€™t nearly as tall.