<P> The height of the Empire State Building, to its 102nd floor, is 1,250 ft (381 m), 1,453 feet 8 ⁄ inches (443.092 m) including its 203 ft (61.9 m) pinnacle . The building has 85 stories of commercial and office space representing a total of 2,158,000 sq ft (200,500 m) of rentable space . It has an indoor and outdoor observation deck on the 86th floor, the highest floor within the actual tower . The remaining 16 stories are part of the Art Deco spire, which is capped by an observatory on the 102nd - floor . The spire is hollow with no floors between levels 86 and 102 . Atop the tower is the 203 ft (61.9 m) pinnacle, much of which is covered by broadcast antennas, and surmounted with a lightning rod . </P> <P> According to the official fact sheets the building rises 1,860 steps from the first to the 102nd floor, weighs 365,000 short tons (331,122 t), has an internal volume of 37,000,000 cubic feet (1,000,000 m), and an exterior with 200,000 cubic feet (5,700 m) of limestone and granite . Construction of the tower required ten million bricks, 370 short tons (330 long tons) of steel, as well as 1,172 miles (1,886 km) of elevator cable and 2,000,000 feet (609,600 m) of electrical wires . The building has a capacity for 20,000 tenants and 15,000 visitors . </P> <P> The building has been named as one of the Seven Wonders of the Modern World by the American Society of Civil Engineers . The building and its street floor interior are designated landmarks of the New York City Landmarks Preservation Commission, and confirmed by the New York City Board of Estimate . It was designated as a National Historic Landmark in 1986 . In 2007, it was ranked number one on the AIA's List of America's Favorite Architecture . </P> <P> The Empire State Building's art deco design is typical of pre--World War II architecture in New York . The modernistic, stainless steel canopies of the entrances on 33rd and 34th Streets lead to two - story - high corridors around the elevator core, crossed by stainless steel and glass - enclosed bridges at the second - floor level . The riveted steel frame of the building was originally designed to handle all of the building's gravitational stresses and wind loads . The exterior of the building is clad in Indiana limestone panels sourced from the Empire Mill in Sanders, Indiana, which give the building its signature blonde color . The limestone facade, which is lined with vertical steel mullions parallel to each window, also helps to increase the stiffness of the steel frame against high winds . The amount of material used in the building's construction resulted in a very stiff structure when compared to other skyscrapers, with a structural stiffness of 42 pounds per square foot (2.0 kPa) versus the Willis Tower's 33 pounds per square foot (1.6 kPa) and the John Hancock Center's 26 pounds per square foot (1.2 kPa). A December 1930 feature in Popular Mechanics estimated that a building with the Empire State's dimensions would still stand even if hit with an impact of 50 short tons (45 long tons). </P>

How many flights of stairs does the empire state building have