Ghalajeh tunnel (Persian: تونل قلاجه) or Arba'een tunnel is a tunnel half of which is located in Eyvan County in Ilam Province and the other half in Gwawar District of Gilan-e Gharb County in Kermanshah Province of Iran. It connects Ilam Province northward to Kermanshah Province. Inaugurated in 2017 with a length of 2.500 meters, it was the third-longest tunnel in Iran. By eliminating Ghalajeh Mountain Pass, the tunnel has made the route 15 Kms shorter.[1][2][3] It is part of road 17 (Iran).