Palmer is composed of four separate and distinct villages: Depot Village, typically referred to simply as "Palmer" (named for the ornate Union Station railroad terminal designed by architect Henry Hobson Richardson), Thorndike, Three Rivers, and Bondsville. The villages began to develop their distinctive characters in the 18th century, and by the 19th century two rail lines and a trolley line opened the town to population growth. Today, each village has its own post office, and all but Thorndike have their own fire station.