Hamlin County is located in the state of South Dakota. It was established in 1873 and is named after Hannibal Hamlin, who served as Vice President under Abraham Lincoln. The county seat is Hayti, which is also its largest city. The county covers an area of approximately 1,200 square miles and is primarily rural, with agriculture being a significant part of its economy. Hamlin County is known for its lakes, including Lake Poinsett, which offers recreational opportunities such as fishing and boating.