Ruy Mountain
 Ruy or Ruj (Bulgarian Cyrillic: Руй Serbian Cyrillic: Руј) is a mountain on the border of western Bulgaria and southeastern Serbia. Its eponymous highest peak rises 1706 meters above sea level. The mountain is located west of Tran and is part of the Ruy-Verila range. On a clear day one can see Rila and Vitosha in Bulgaria and Veliki Štresar in Serbia.