Stewards of the iconic buildings and grounds of Capitol Hill since 1793.

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National Statuary Hall
The National Statuary Hall Collection in the United States Capitol Building is...

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A crowd of people visiting the Capitol during visitor hours
Visitor Hours for the Buildings on Capitol Hill.

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Photo with enclosed area on Dome.
Update: November 2014 Scaffoldin​g and Restoring PhaseThe scaffolding assembly...

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AOC employee working on touching up columns in Statuary Hall
Next time you're in Statuary Hall on the second floor of the U.S. Capitol...

Dome By-The-Numbers

Dome By-The-Numbers

Dome Restoration

Rendering of the Dome Restoration Project
  • 1.1 million lbs. weight of scaffold
  • 75,000+ pieces of equipment
  • 52 miles of scaffold pipe
  • 2 miles of decking, enough to build a sidewalk 5 feet wide x 2 miles long from the US Capitol to the Lincoln Memorial
  • 5 layers of safety netting in Rotunda
  • 14,700 square feet total Rotunda safety netting, approximately the size of two tennis courts
  • 6,100 lbs. total weight of Rotunda netting
  • 12,800 inches of cracked cast iron will be repaired (8,200 inches will be repaired with the "lock and stitch" technique, 4,600 inches will be repaired with the "Dutchman" technique)
  • 1,215 gallons of paint will be used to repaint the Dome - 3 layers x 405 gallons each. Final top coat color is "Dome White."

 


Dome Weight

  • 8,909,200 pounds weight of Dome = approximately 4,500 tons = about the same weight of 20 Statues of Liberty 

Dome Exterior Height

  • 376 feet height above Potomac River (includes Hill elevation)
  • 288 feet height above East Front Plaza including Statue of Freedom, is the tallest cast iron dome in world approximate height 29 story building
  • 210 feet height above East Front Plaza to the balcony used for Dome tours at Tholos 
  • 199 feet height of Dome measured from Dome Skirt to Base of Freedom
  • 555 feet height of the Washington Monument is 267 feet taller than the U.S. Capitol. Because the base of the Washington Monument is 30 feet above sea level, and that of the Capitol is 88 feet above sea level, the top of the Washington Monument is 209 feet higher than the top of the Capitol Building.
a technical drawing of the Capitol Dome and its interior

Dome Diameter

  • 135 feet measured from exterior
  • 96 feet measured from interior 

Rotunda

  • 180 feet from Rotunda floor to top of the Apotheosis; the Statue of Liberty without her base would fit with room to spare (she is 151 ft)
  • 85 feet from Rotunda floor to first visitor gallery
  • 149 feet from the Rotunda floor to the second visitor gallery
  • 20 feet from the bottom edge of the Apotheosis to the apex at the center of the hemisphere  

Windows 

  • 108 in Dome
  • 36 windows in Cuploa
  • 36 windows in second story
  • 36 windows in Peristyle
  • 12 windows in Tholos

Iron

  • 36 hollow cast-iron columns in peristyle set 10 degrees apart around 360-degree circle
  • 12 columns in Tholos
  • 14 over lapping cast-iron plates make up one section Copula
  • 3/8" to 1/2 " range of thickness of cast iron in Dome
  • 5/8" thickness of cast-iron in the Dome Skirt

An image that shows the size comparison between an up-facing acorn and a basketball

Decorative Features

  • 288 balusters in Boiler Plate Balustrade
  • 80 lbs. approximate weight of decorative acorns
  • 72 acorns total decorative acorns
  • 36 up-facing acorns  
  • 36 down-facing acorns 
  • 36 grape clusters
  • 4 300 watt “in-session” light bulbs Tholos

Statue of FreedomA detailed diagram of the Statue of Freedom

Weight

  • 15,000 pounds = approximate weight of 4 cars

Height

  • 38 feet tall Statue of Freedom with base = approximately as high 4 story building
  • 19.5 feet statue height without pedestal
  • 18.5 feet height of pedestal

Base

  • 12 wreaths are on the base of the Statue of Freedom
  • 12 fasces, symbols of legislative authority, are above the wreaths

Headdress

  • 10 lighting rod points sit atop Freedom’s Roman inspired headdress with native American influences