The mausoleum-ossuary was built in the neo-Byzantine style, as a commemorative monument, between 1903 and 1907 when it was inaugurated by Prince Ferdinand I of Saxe-Coburg-Gotha. The interior contains a chamber in the shape of a Greek cross closed off by an iconostasis carved by Ivan Travnitzki. The decorative icons are believed to be the work of Ivan Markvicka (1856-1938) and Anton Mirov (1862-1930). The three large murals date from 1977. The crypt houses collective tombs containing the remains of Russian and Romanian soldiers who gave their life for Pleven.