Alden is a city in Freeborn County, Minnesota, United States. The population was 661 at the 2010 census. A post office called Alden ha…Alden is a city in Freeborn County, Minnesota, United States. The population was 661 at the 2010 census. A post office called Alden has been in operation since 1866. Alden was platted in 1869 when the railroad was extended to that point. Edmond Conn, farmer, businessman, and politician, was born in Alden.