Columbia Falls, in Flathead County...
There are many stories about why the town was named as it is. One of the most credible stories comes from Names on the Face of MONTANA
by Roberta Carkeek Cheney
Mountain Press Publishing Company
Missoula, Montana, 1983 [ISBN 0-87842-150-5]:
"...when the Great Northern Highline was built, the town of Columbia was proposed as a division point, but when property owners demanded exorbitant prices for the land, Jim Hill rechristened the town Columbia Falls and the new town of Whitefish was made division headquarters. The town [Columbia Falls] had been platted on a scale that proved too generous when it failed to get the railroad division point. Excellent sidewalks extend some distance beyond the built-up area. J.P Rowe says that the townsite was originally planned for a place near the falls on the Flathead River which is part of the headwaters of the Columbia River -- hence the name Columbia Falls. Postal records say an office was established under this name in 1891 with James Kennedy as postmaster, and that it was formerly known as Monaco."