Geologists say that the falls first appeared roughly 12,000 years ago about downstream at the confluence of the glacial River Warren (at present-day Ft. Snelling). Estimates are that the falls were about high when the River Warren Falls receded past the confluence of the Mississippi River and the glacial River Warren. Over the succeeding 10,000 years, the falls moved upstream to its present location. The water churning at the bottom of the falls ate away at the soft sandstone, eventually breaking off the hard limestone cap in chunks as the falls receded. From its origins near Fort Snelling, St. Anthony Falls relocated upstream at a rate of about per year until it reached its present location in the early 19th century. Tributaries such as Minnehaha Creek begot their own waterfalls as the Mississippi River valley was cut into the landscape.