Pike's Mile Markers are a series of twelve stone mileposts along United States Route 1 in Robbinston and Calais in far eastern Washington County, Maine. The stones were placed by James Shepherd Pike, owner of The Mansion House which stands near the 12-mile mark. The measure the distance from his house to the center of Calais, and were supposedly used by Pike to assess the quality of his horses. The markers, unique in the state of Maine, were listed on the National Register of Historic Places in 1995.