The Hyderabad Airport Express Metro or Corridor IV was a planned Hyderabad Metro line from Raidurg metro station to Rajiv Gandhi International Airport. The total length of the line is 31 km (19 mi). Hyderabad Airport Express Metro is fully funded by Government of Telangana through the engineering, procurement and construction (EPC) mode. As of December 2023, Union Government is yet to provide in principle approval for this project.

The Airport Express Line or Orange Line is a Delhi Metro line from New Delhi to Yashobhoomi Dwarka Sector - 25, linking Indira Gandhi International Airport. The total length of the line is 22.7 km (14.1 mi), of which 15.7 km (9.8 mi) is underground and 7.0 km (4.3 mi), from Buddha Jayanti Park to Mahipalpur, elevated.