Arch Falls is a waterfall on Hyalite Creek in Gallatin County, Montana, in the Middle Rockies region, with a total height of about 30 feet. It lies about 17.8 miles south of Bozeman and roughly 121.4 miles west of Billings as the crow flies.
At 30 feet it is on the modest side for Montana, where the typical waterfall with a recorded height stands around 250 feet; it ranks 113th of 123. The water comes down as a plunge, where the water drops vertically and loses contact with the rock face.
The Middle Rockies are high, glaciated mountain ranges with alpine peaks, subalpine fir and spruce forest, lodgepole pine and grassy intermontane valleys. Snowmelt streams cascade down glacial valleys and canyon walls. Hyalite Creek carries 5 recorded waterfalls; the biggest of them reaches 80 feet.
There are 14 recorded waterfalls in Gallatin County. Grotto Falls, a 40-foot fan waterfall, is under a mile away. Maid of the Mist Creek Falls, a 600-foot tiered waterfall, is under a mile away. Silken Skein Falls, a 240-foot tiered waterfall, is under a mile away.
Arch Falls is located at 45.4275° N, 110.9611° 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.