The spot where the trail crossed the Cedar River was known by the early pioneers as Prairie Rapids Crossing. Nearly everywhere along the river the banks were wooded. But, here at the ford the bank was open prairie for about half a mile in either direction; hence its name.

It is here that Waterloo began with its first homes and businesses built in this area. The first log cabin in the new town was built by George Hanna in 1852 on the present site of the Waterloo Savings Bank. Sam Aldrich built a cabin nearby in the same year, and Sam Ayers built on the opposite bank in 1853. Ayers took in boarders, as did Samuel May, who also operated a ferry during periods of high water. The first store was operated by Nelson Fancher where the Waterloo Public Library now stands. When Charles Mullan applied for a post office the town acquired mail service (as well as its present name).

The first dam was built here in 1854, made of logs and brush. It raised the water level two feet, making it possible to operate a saw mill. A flour mill was built two years later, placing Waterloo in competition with Cedar Falls for the local milling business.

The first bridge over the Cedar River at this spot was a footbridge built in 1856 at 5th Street. A wagon bridge was built at 4th Street by miller George Couch in 1856, using timber cut on Charles Mullan's farm.

Thus it was that a shallow place in the river, with a rocky bottom, became the heart of a city. As the focus for east-west travel, it was natural that homes, businesses and transportation would center on this spot, as they have ever since.