Physical Characteristics. Collier County is in southwest Florida and is bordered by the Gulf of Mexico, and by Lee, Broward, Monroe, and Dade counties. The county has 1994.10 square miles of land and 112.80 square miles of water for a total of 2106.90 square miles. The average January temperature is 67.8 degrees Fahrenheit, and the average August temperature is 82.4 degrees Fahrenheit. The average annual rainfall is 51.40 inches.
History. Collier County was established from a portion of Lee County in 1923 and named for advertising tycoon Barron G. Collier, one of South Florida's leading developers.
