In which country would you find the largest building in the world by volume?

The Boeing Everett Factory, in Everett, Washington, USA, is an airplane assembly building owned by Boeing. Located on the northeast corner of Paine Field, it is the largest building in the world by volume at 13,385,378 m3 (472,370,319 cu ft) and covers 399,480 m2 (98.7 acres). It even has its own micro-climate. This is the factory where the wide-body Boeing 747, 767, 777, and 787 are assembled.

Plans for the factory were first announced in 1966 for it to be the site of the construction of the 747 after Boeing was awarded a $525 million contract from Pan American World Airways to build twenty-five 747s. It purchased 780 acres north of the then little-used Paine Field, which was operated by the US Army in World War II.

In 1968 it began offering factory tours with the first roll out of the 747. Over 150,000 people visit the Everett Site each year. The factory includes a BECU branch and several cafés. Across the airport to the west is The Boeing Store, a theater, and a Future of Flight Aviation Center, which runs the factory tour. The Everett Factory employs over 30,000 people, including its own fire department, security team, daycare center and fitness center.