Navi Mumbai International Airport — Navi Mumbai, India

Mumbai's existing airport has operated for years beyond the traffic levels it was originally designed to handle, and Navi Mumbai International Airport was conceived to ease that pressure with a second major gateway for the metropolitan region. NMI sits across the harbor from South Mumbai in the planned township of Navi Mumbai, on a site requiring extensive earthworks, river diversion, and the leveling of hills before construction could proceed, reflecting the scale of engineering involved in fitting a major airport into the crowded Mumbai Metropolitan Region. Plans call for multiple runways and terminal capacity built out in phases, eventually aiming to handle a very large volume of passengers annually alongside the older Chhatrapati Shivaji Maharaj International Airport across the water. Developed through a public-private partnership involving the Adani Group in its later stages, the project has been framed by officials as essential infrastructure for a metropolitan area whose economic weight and growth have long outpaced its aviation capacity.