Following the addition of primary and secondary hubs to the airline network during the 1990s, for much of the next decade, additional demand led to massive expansion of its central Louisville air hub. From 1999 to 2002, in a $1 billion expansion, the Louisville hub was doubled in size (to 4 million square feet), with the hub adapting the name of the expansion project, Worldport. As part of the 2004 purchase of Menlo Worldwide Forwarding, a second expansion was completed in 2006 to expand heavy-freight operations in the UPS systems; similar expansions were added to the largest UPS hubs in the United States. From 2006 to 2010, a third expansion added over 1 million square feet to the Worldport facility (to 5.2 million square feet) and added additional ramp space for aircraft.