14,000 years ago

Clear Lake is a spring-fed lake formed by glacial action; it has a surface area of about 3600 acres. It is more than six miles long and two and a half miles wide. The elevation is 1247 feet above sea level and it is nearly 100 feet above the nearby countryside, which gives it the appearance of a saucer sitting above the surrounding area.

1832

Clear Lake was a favorite summer camping ground of both the Sioux and Winnebago native tribes. The first-known recorded mention of the body of water known as Clear Lake was in a land survey of northern Iowa, done in 1832. This map, with the survey, is signed by land surveyor, Nathan Boone, son of the famous explorer, Daniel Boone. Streams and rivers of the area are shown as well as the lake.