Question: What is the size of the purpose of the largest United States building on this list of Megastructures S2 ?

text: Megastructures
Episodes -- Season 2 ( 2005 )

Megastructures is a documentary television series appearing on the National Geographic Channel in the United States and the United Kingdom, Channel 5 in the United Kingdom, France 5 in France, and 7mate in Australia. Each episode is an educational look of varying depth into the construction, operation, and staffing of various structures or construction projects, but not ordinary construction products. Generally containing interviews with designers and project managers, it presents the problems of construction and the methodology or techniques used to overcome obstacles. In some cases (such as the Akashi-Kaikyo Bridge and Petronas Towers) this involved the development of new materials or products that are now in general use within the construction industry. Megastructures focuses on constructions that are extreme; in the sense that they are the biggest, tallest, longest, or deepest in the world. Alternatively, a project may appear if it had an element of novelty or are a world first (such as Dubai's Palm Islands). This type of project is known as a megaproject. The series follows similar subjects as the History Channel's Modern Marvels and Discovery Channel's Extreme Engineering, covering areas of architecture, transport, construction and manufacturing.
# Country Title Subject Original Airdate
01 United States Golden Gate Bridge Iconic bridge over San Francisco Bay in San Francisco 2005-03-02
02 United States Alcatraz Former prison island in San Francisco Bay , California 2005-03-16
03 United States Inside The Pentagon Headquarters of the US Department of Defense in Arlington , Virginia 2005-04-01
04 Singapore World 's Busiest Port Port of Singapore , Republic of Singapore 2005-05-13
05 South Africa Tau Tona , City of Gold World 's deepest mining operations in Carletonville , South Africa 2005-05-21
06 United States Las Vegas  2005-06-22
07 Canada Black Gold ( Oil Mine ) Syncrude and Shell Canada in oil sands located in Alberta , Canada 2005-07-20
08 Canada Diamond Diggers Ekati Diamond Mine , Canada 's first diamond mine , near Lac De Gras , Northwest Territories , Canada 2005-07-27
09 United States Sea Launch Ocean Odyssey and Sea Launch Commander 2005-08-03
10 Netherlands North Sea Wall Delta Works 2005-08-17
11 United Arab Emirates The World 's Most Extreme Island ( Impossible Islands ) Dubai 's artificial palm islands , United Arab Emirates 2005-09-13
12 United States Indianapolis Motor Speedway Car racetrack in Speedway , Indiana 2005-09-13
13 Netherlands Port of Rotterdam ( Super Port ) The largest port in Europe , in Rotterdam , Netherlands 2005-09-20
14 United States Air Force Transport ( Mega Plane ) C-5 Galaxy with the U.S. Air Force 2005-09-20
15 United States North Branch Correctional Institution ( Hi-Tech Prison ) High Security Prison , Allegany County , Maryland 2005-09-27
16 France Airbus A380 ( World 's Biggest Airliner ) Biggest jumbo jet in commercial service 2005-10-04
17 United States USS Virginia Virginia -class submarine with the U.S. Navy 2005-10-11
18 United States Ultimate Casino Venetian Hotel Resort Casino in Las Vegas , Nevada 2005-10-18
19 United States The Ultimate Roller coaster Kingda Ka roller coaster at Six Flags Great Adventure theme part in Jackson , New Jersey 2005-10-25
20 United States Spy Fortress NORAD North American Aerospace Defense Command , Colorado 2005-10-25