The most extensive network of ATMs belongs to the savings banks associations ("Sparkassen") with 24,600 ATMS. Most of the private banks are either member of the Cash Group (7,000 ATMs owned by the major banks) or Cash Pool (2,500 ATMs owned by smaller banks) – they are usually found in city centers. The credit unions ("Volksbanken" and "Raiffeisenbanken") provide around 18,000 ATMs and are associated in the BankCard ServiceNetz, very often in smaller towns and villages, but less frequently available in the big cities.