Chapel "St. 40 Martyrs" is located on a hill (283 m) in the "Hasar" locality, southeast of village of Stalevo. This is a historical place. From here, in 1230, Tzar Ivan Assen II led the Klokotnitsa battle, when Bulgarians defeated the Byzantine army of Emperor Theodore Comnenus. It is believed that the stones in the area are part of the Thracian fortress and sanctuary Mileona.