President Recep Tayyip Erdogan opened Istanbul’s new airport with a pledge that it would become the world’s biggest and serve as a symbol of prosperity for a country he hopes will become a global power.

The $11.7 billion airport crowns an infrastructure-building spree that has transformed the Turkish landscape and economy during Erdogan’s 15 years in power. But the megaproject has been tarnished by environmental degradation and labor protests over poor working conditions that led to dozens of deaths.

A crowd of thousands watched on screens as Erdogan’s jet touched down at the airport and he strode through the vaulted international terminal. Despite a race to finish it under four years, the full opening had to be delayed this month and the airport will only operate a handful of routes until the end of this year.

The lavish opening ceremony, which coincided with the 95th anniversary of the founding of the Turkish Republic on Monday, was attended by a half-dozen world leaders including Sudan’s Omar al-Bashir. Speakers praised Erdogan for his vision in realizing an unprecedented engineering feat that included moving 750 million cubic meters of soil — the equivalent of eight Suez Canals, according to an introductory video.