The city is in the westernmost part of Saitama. Unlike other parts of the prefecture, it is largely mountainous and the population is concentrated in river terraces along the Arakawa River. It is Saitama's largest municipality in terms of surface area and shares borders with Tokyo, Yamanashi, Nagano and Gunma prefectures. A large portion of the city belongs to Chichibu-Tama-Kai National Park.
Because the region is not suitable for growing rice, many people have depended on sericulture farming. Limestone from Mount Bukô, which rises south of the city center, is another major source of income for the region. The city is shifting its focus toward sightseeing, taking advantages of its rich natural environment and relative closeness to the Tokyo metropolitan area. The city is also famous for its brewing industry.