The Turkmen people have traditionally been nomads and equestrians, and even today after the fall of the USSR attempts to urbanize the Turkmens have not been very successful. They never really formed a coherent nation or ethnic group until they were forged into one by Joseph Stalin in the 1930s. Rather they are divided into clans, and each clan has its own dialect and style of dress. Turkmens are famous for making ''knotted Turkmen carpets'', often mistakenly called ''Bukhara rugs'' in the West. These are elaborate and colorful hand-knotted carpets, and these too help indicate the distinctions among the various Turkmen clans. Ethnic groups throughout the region build yurts, a circular houses with dome roofs, made of a wooden frame covered in felt from the hides of sheep or other livestock. Horses are an essential ingredient of recreational activities in most of the region, in such games as horseback fighting, in which riders grapple to topple each other from their horses; horse racing.