A roadside marker is an object placed along the side of a road to provide information or guidance to travelers. The most common roadside markers are cones, signs, and mileposts. A CONE is a three-dimensional object with a circular base and a pointed top, typically used to mark a hazard or obstruction. Signs are flat objects with words or symbols on them, used to convey information or instructions. Mileposts are markers that indicate the distance from a certain point, usually the beginning of a route. Together, these three roadside markers provide travelers with important information about their journey.