A typical gord was a group of wooden houses built either in rows or in circles, surrounded by one or more rings of walls made of earth and wood, a palisade, and/or moats. Some gords were ring-shaped, with a round, oval, or occasionally polygonal fence or wall surrounding a hollow. Others, built on a natural hill or a man-made mound, were cone-shaped. Those with a natural defense on one side, such as a river or lake, were usually horseshoe-shaped. Most gords were built in densely populated areas on sites that offered particular natural advantages.