Spokane’s Natatorium Park was one of the earliest amusement parks in the Northwest. The Park was located on the Spokane River where it begins a big “S” curve. It was several miles from the center of town at the end of Boone Avenue. The park was originally called Ingersoll Park which had a picnic area near the river. In 1887, a Spokane capitalist by the name of Sherwood, financed a cable car line across the first wooden Monroe Street Bridge. The cable car needed a destination at the end to attract riders. So they installed a baseball field that opened on July 18, 1889.
The park was very crowded on baseball days but empty at other times. A year later, a casino and bar opened there on July 26, 1890. The name was changed to Twickenham Park after a housing development of the same name.
In 1893, the Spokane Street Railway, which was owned by the Washington Water Power Company (WWP), bought the entire park and decided to expand it into an amusement park patterned after Coney Island. They built a swimming pool next to the river and set about to rename the park. They stumbled across the Latin word for an indoor swimming pool – natatorium. Over the years, the park became known as Nat Park.