Gravel Bikes are primarily designed to be ridden on gravel and fire roads. Like cyclocross bikes, they usually feature disc brakes, a high bottom bracket and big tire clearance. What sets a Gravel Bike apart though is the geometry. Gravel bikes usually have more relaxed endurance-type geometry with a taller head tube, sloping top tube, and longer wheel base for improved comfort over long distances. The head tube angle is also a little slacker, and the chain stays longer, to give you more stability on uneven surfaces.