A waterfall is usually a geological formation resulting from water, often in the form of a stream, flowing over an erosion-resistant rock formation that forms a sudden break in elevation or nickpoint.
Some waterfalls form in mountain environments where the erosive water force is high and stream courses may be subject to sudden and catastrophic change. In such cases, the waterfall may not be the end product of many years of water action over a region, but rather the result of relatively sudden geological processes such as landslides, faults or volcanic action.
Waterfalls may also be artificial, and they are sometimes created as garden and landscape ornaments.
Tahquamenon Falls Upper Falls, Upper Peninsula, Michigan
Proxy Falls, Willamette National Forest, Oregon
Ramona Falls, Mount Hood Wilderness, Oregon
Peaceful Waters, Colorado River, Colorado
Paradise River, Mount Rainier National Park, Washington
Paradise River Waterfall, Washington
Victoria Falls, Zimbabwe, Africa
Tangle Creek Falls, Jasper National Park, Canada
Yellowstone Falls, Yellowstone National Park, Wyoming
Waterfall, Palau, Micronesia
Waterfall, Letchworth State Park, New York