Fifteenmile Falls is a waterfall on Fifteenmile Creek in King County, Washington, in the Cascades region. It lies about 1.5 miles north of Mirrormont and roughly 10.7 miles east of Renton as the crow flies.
Its height has not been recorded in the source data.
The Cascades are a high volcanic range of snow-capped peaks, deep glacial valleys and dense conifer forest of Douglas fir, western hemlock and true firs, with abundant rain and snow on the western slopes. Basalt cliffs and lava flows give the region one of the highest concentrations of waterfalls in the country. Fifteenmile Creek carries 2 recorded waterfalls along its course.
King County holds 236 recorded waterfalls, and several are close by. Shaun Falls, is about 4.3 miles away. Laughing Jacobs Falls, a 20-foot cascade waterfall, is about 6.2 miles away. Doughty Falls, a 10-foot horsetail waterfall, is about 6.2 miles away.
Fifteenmile Falls is located at 47.4830° N, 121.9882° W. The listing is based on the World Waterfall Database, one of the sources compiled by the U.S. Geological Survey in its inventory of waterfalls and rapids of the conterminous United States. The creek name is confirmed against the federal Geographic Names Information System. The exact position has not yet been verified on aerial imagery, so treat the map pin as approximate. Details on trails, parking and access have not been documented for this waterfall yet.