Mashhad Metro is a light rail system operating in the holy city of Mashhad, in the Razavi Khorasan province of Iran. The city of Mashhad is spread over 270km² and has a population of 5.2 million. Comprehensive studies for the construction of a new urban railway line were conducted during 1994-1999 and 2002-2004, highlighting the requirement for four new urban rail lines in Mashhad.