Three decades ago, Doha in Qatar, and Dubai and Abu Dhabi in the United Arab Emirates were little known outside the Persian Gulf.

Today, they’re among the world’s fastest-growing and wealthiest cities. And for international air travelers, they represent a new crossroads of the aviation world. They’re home to hubs of three fast-growing airlines — Qatar Airways, Emirates and Etihad Airways — that are going toe to toe with the world’s more-established giants.

They’ve turned their focus on the United States after expanding at breakneck speed in Asia, Africa and Europe. They’re increasingly flying to more U.S. cities with greater frequency.

Photo Credit: A Qatar Airways flight takes off from Soekarno-Hatta International Airport in Jakarta, Indonesia. Luke Ma / Flickr.com