Frostproof is a city in Polk County, Florida, United States. The city is located in southern Polk County located on the Lake Wales Ridge. The population was 2,975 at the 2000 census. As of 2004, the population recorded by the U.S. Census Bureau is 2,954. It is part of the Lakeland–Winter Haven Metropolitan Statistical Area.
The first white settlement in the area now known as Frostproof was established in 1850. This settlement like many on central Florida at the time was set up as a fort and was called Fort Cinch. This settlement did not last long and was abandoned only months later. By the 1880s, Frostproof began to see its first permanent settlers as homesteaders were attracted to the abundant hunting in the area which included much deer and turkey, as well as ample fishing.
The name was a marketing ploy to convince potential landowners that the town has never had, and never would have, a frost that could destroy the large citrus-driven economy. However, only a couple of years later, a terrible frost killed most of the citrus in Frostproof. Prior to being named Frostproof, the town was named Keystone City. However, after being confused regularly with Keystone Heights, a city in North Florida, Frostproof was coined.