Archeologists discovered a unique fortress from the First Bulgarian Kingdom after two year research. The unknown fortifying and living structure is near the village Ruino, near Dulovo in the Silistra region, in northeastern Bulgaria. A 4-meters deep moat provided additional defense. A 50 decares village was found several days ago too. Georgi Atanassov, who led the research, said that an international expedition should be formed to research the archeological sites in Moldova and Ukraine in connection with the Bulgarian history.