Iran lies at the crossroads of East-West and North-South transportation. The railway network connects all major parts of the country. The western railway extension links to Turkey at the Razi–Kapikoi border. A northern connection to Azerbaijan, the Caucasus, and Russia has a bogie-changing station at the border at Jolfa.

The southern routes connect Tehran to the Persian Gulf ports of Bandar Imam and Bandar Abbas. A line to the Caspian Sea ends at the terminal of Amir Abad and at Bandar Torkaman, and is part of a North-South corridor to Russia and Scandinavia. The north-east corridor connects Mashad and continues further to the bogie-changing station at Sarakh. For the landlocked countries of Turkmenistan, Uzbekistan, Tajikistan, Kyrgyzstan, and Kazakhstan, this line provides access to the sea. A recent connection from Mashad to Bafqh has significantly shortened access to the port city of Bandar Abbas.