the Mongol invasion of Volga Bulgaria. References Edward Tracy Turnerelli, Kazan, the Ancient Capital of the Tartar Khans, 1854, pp 196-261 External links Populated places on the Volga Defunct towns in Russia Islam in Russia Archaeological sites in Tatarstan Volga Bulgaria Former populated places in Russia World Heritage Sites in Russia Cultural heritage monuments of federal significance in Tatarstan bg:Болгар (град)