The Aladagh Mountains or the Aladagh Range refers to a mountain range situated in the southeastern section of North Khorasan Province in the northeastern part of Iran southeast of the Caspian Sea. The range is located almost 25 kilometres south of Bojnurd, the capital city of North Khorasan. The Aladagh Mountains merge with the Elburz or Alborz Mountains in the west and then run southeastwards in a northwest-southeast direction. The highest peak of the range is Mount Shahjahan with an elevation of 3032 metres. This peak is located about 35 kilometres east of Esfarayen almost in southeastern part of North Khorasan Province.