From 1998 to 2011, the Pentagon underwent a major renovation, known as the Pentagon Renovation Program. This program, completed in June 2011, involved the complete gutting and reconstruction of the entire building in phases to bring the building up to modern standards, removing "asbestos, improving security, providing greater efficiency for Pentagon tenants, and sealing of all office windows.
As originally built, most Pentagon office space consisted of open bays which spanned an entire ring. These offices used "cross-ventilation from operable windows instead of air conditioning for cooling. Gradually, bays were subdivided into private offices with many using "window air conditioning units. With renovations now complete, the new space includes a return to open office bays, a new Universal Space Plan of standardized office furniture and partitions developed by Studios Architecture.
September 11 attacks
On September 11, 2001, the 60th anniversary of the Pentagon's groundbreaking, a team of five "al-Qaeda affiliated hijackers took control of "American Airlines Flight 77, en route from "Washington Dulles International Airport to "Los Angeles International Airport, and deliberately crashed the "Boeing 757 airliner into the western side of the Pentagon at 9:37 am EDT as part of the "September 11 attacks. All 59 civilians and the 5 terrorists on the airliner were killed, as were 70 civilians and 55 military personnel who were in the building. The impact of the plane severely damaged the outer ring of one wing of the building and caused its partial collapse. At the time of the attacks, the Pentagon was under renovation and many offices were unoccupied, resulting in fewer casualties. Only 800 of 4,500 people who would have been in the area were there because of the work. Furthermore, the area hit, on the side of the Heliport facade, was the section best prepared for such an attack. The renovation there, improvements which resulted from the "Oklahoma City bombing, had nearly been completed.
It was the only area of the Pentagon with a sprinkler system, and it had been reconstructed with a web of steel columns and bars to withstand bomb blasts. The steel reinforcement, bolted together to form a continuous structure through all of the Pentagon's five floors, kept that section of the building from collapsing for 30 minutes—enough time for hundreds of people to crawl out to safety. The area struck by the plane also had blast-resistant windows—2 inches thick and 2,500 pounds each—that stayed intact during the crash and fire. It had fire doors that opened automatically and newly built exits that allowed people to get out.
Contractors already involved with the renovation were given the added task of rebuilding the sections damaged in the attacks. This additional project was named the ""Phoenix Project," and was charged with having the outermost offices of the damaged section occupied by September 11, 2002.
When the damaged section of the Pentagon was repaired, a small indoor memorial and chapel were included, located at the point of impact. For the fifth anniversary of the September 11, 2001 attacks, a memorial of 184 beams of light shone up from the center courtyard of the Pentagon, one light for each victim of the attack. In addition, an American flag is hung each year on the side of the Pentagon damaged in the attacks, and the side of the building is illuminated at night with blue lights. After the attacks, plans were developed for an outdoor memorial, with construction underway in 2006. This "Pentagon Memorial consists of a park on 2 acres (8,100 m2) of land, containing 184 benches, one dedicated to each victim. The benches are aligned along the line of Flight 77 according to the victims' ages, from 3 to 71. The park opened to the public on September 11, 2008.
On March 4, 2010, at 6:40 pm, two police officers working for the "Pentagon Force Protection Agency were shot near an entrance to the Pentagon and fired back with their pistols at the suspect. The officers were slightly injured but were treated in a hospital and released. The suspect, identified as "John Patrick Bedell (age 36), died at the hospital. No clear motive was established. On October 19, 2010, shortly before 5 am, an unidentified gunman shot at the south side of the building, shattering windows on the third and fourth floors.
On August 23, 2011, a 5.8 magnitude earthquake in "Mineral, Virginia, shook the Pentagon. The building suffered minor damage, with flooding from broken pipes.
The Pentagon building spans 28.7 acres (116,000 m2), and includes an additional 5.1 acres (21,000 m2) as a central courtyard. Starting with the north side and moving "clockwise, its five façades are the Mall Terrace Entrance façade, the River Terrace Entrance façade, the Concourse Entrance (or Metro Station) façade, the South Parking Entrance façade, and the Heliport façade. On the north side of the building, the Mall Entrance, which also features a portico, leads out to a 600 ft (180 m) long terrace that is used for ceremonies. The River Entrance, which features a "portico projecting out 20 ft (6.1 m), is located on the northeast side, overlooking the lagoon and facing Washington. A stepped terrace on the River Entrance leads down to the lagoon; and a landing dock was used until the late 1960s to ferry personnel between "Bolling Air Force Base and the Pentagon. The main entrance for visitors is located on the southeast side, where the "Pentagon Metro station and the bus station are located. There is also a concourse on the southeast side of the second floor of the building, which contains a mini-shopping mall. The Pentagon's south parking lot is located on the southwest side of the Pentagon, and the west side of the Pentagon faces "Washington Boulevard.
The concentric rings are designated from the center out as "A" through "E" (with in addition "F" and "G" in the basement). "E" Ring offices are the only ones with outside views and are generally occupied by senior officials. Office numbers go clockwise around each of the rings, and have two parts: a nearest-corridor number (1 to 10) followed by a bay number (00 to 99), so office numbers range from 100 to 1099. These corridors radiate out from the central courtyard, with corridor 1 beginning with the Concourse's south end. Each numbered radial corridor intersects with the corresponding numbered group of offices (for example, corridor 5 divides the 500 series office block). There are a number of historical displays in the building, particularly in the "A" and "E" rings.
Floors in the Pentagon are lettered "B" for Basement and "M" for "Mezzanine, both of which are below ground level. The concourse is located on the second floor at the Metro entrance. Above ground floors are numbered 1 to 5. Room numbers are given as the floor, concentric ring, and office number (which is in turn the nearest corridor number followed by the bay number). Thus, office 2B315 is on the second floor, B ring, and nearest to corridor 3 (between corridors 2 and 3). One way to get to this office would be to go to the second floor, get to the A (innermost) ring, go to and take corridor 3, and then turn left on ring B to get to bay 15.
It is possible for a person to walk between any two points in the Pentagon in less than seven minutes.
Just south of the Pentagon are "Pentagon City and "Crystal City, extensive shopping, business, and high-density residential districts in "Arlington. "Arlington National Cemetery is to the north. The "Washington Metro "Pentagon station is also located at the Pentagon, on the "Blue and "Yellow Lines. The Pentagon is surrounded by the relatively complex "Pentagon road network.
The "United States Postal Service has established six "ZIP Codes for The Pentagon, to which the place name “Washington, D.C.” is assigned, even though The Pentagon is actually located in "Virginia. The Secretary of Defense, the Joint Chiefs of Staff, and the four service branches each have their own designated ZIP Code.
The "Pentagon Force Protection Agency (PFPA) is a United States government agency composed of sworn "federal police officers, the "United States Pentagon Police and civilian "CBRN technicians, and non-sworn civilian "anti-terrorism investigative and physical "security personnel, and is responsible for the protection of the Pentagon. The Department of Defense created the PFPA after the "September 11, 2001 attacks. The new agency absorbed the Defense Protective Service (DPS) and assumed its role of providing basic "law enforcement and security for the Pentagon and Department of Defense sites in the 280 acre (1.1 km2) "Pentagon Reservation" and greater "National Capital Region (NCR). PFPA was also charged with providing force protection against the full spectrum of potential threats through robust "prevention, "preparedness, detection, and "response measures. The "United States Pentagon Police is the primary federal law enforcement arm of the Pentagon Force Protection Agency.
Hall of Heroes
Located on the Pentagon's main concourse is the Hall of Heroes, a room dedicated to the more than 3,460 recipients of the "Medal of Honor, the United States' highest military decoration.  There are three different versions of the Medal of Honor: the Army version, the Sea Service version (Marine Corps, Navy and Coast Guard), and the Air Force version. All three versions are displayed in the Hall of Heroes. Along the walls of the room are the names of each recipient. An asterisk next to some of the names denotes service members who received two Medals of Honor for two separate acts of bravery. Dots next to other names denote Marines who were under the command of the Army during World War I and received both the Army and Sea Service versions of the Medal of Honor for a single act of bravery. The Hall of Heroes was opened during a Medal of Honor awards ceremony on May 14, 1968. President "Lyndon Johnson officiated the ceremony and awarded the Medal of Honor to four serviceman: "Specialist 5 "Charles C. Hagemeister, "U.S. Army; "Sergeant "Richard A. Pittman, "U.S. Marine Corps; "Boatswain's Mate 1st Class "James E. Williams, "U.S. Navy and "Captain "Gerald O. Young, "U.S. Air Force. It was the first time that all four services were represented in a Medal of Honor Ceremony. The medals were awarded in the Pentagon's center courtyard. Upon the ceremony's conclusion, President Johnson ascended a staircase to his rear and cut a red ribbon in front of a door at the top of the stairs providing entrance to the Hall of Heroes. At the time of the dedication, the Hall of Heroes was located on the Pentagon's second floor, A Ring, overlooking the courtyard. As part of the Pentagon's renovation, the Hall of Heroes was moved to its current location on the main concourse.
The Hall of Heroes is also used for promotions, retirements, and other types of award ceremonies.
The Pentagon has over 20 of its own fast food operations, including "Subway, "McDonald's, "Dunkin' Donuts, "Panda Express, "Starbucks and "Sbarro, among others. A "multibranded "KFC, "Pizza Hut, and "Taco Bell restaurant opened in 2003, when renovations to the food court were completed. Food services are managed by the "Navy Exchange. The Center Courtyard Cafe reopened in the spring of 2008, replacing the "Ground Zero Cafe" snack bar that was previously there.
The Pentagon Athletic Center (PAC), a "fitness center for military and civilian staff, opened in 2004 adjacent to the north side of the Pentagon, replacing the Pentagon Officers Athletic Club (POAC) which had operated for 55 years in a structure between Route 110 and the parade grounds. Each year, the Pentagon grounds are a major focus for hosting the "Marine Corps Marathon and the "Army Ten-Miler running events.
There is a "Meditation and "Prayer Room in the Pentagon, which was dedicated on December 14, 1970, by Secretary of Defense "Melvin Laird. On September 11, 2002 the Pentagon Memorial Chapel was dedicated.
In conjunction with the 1976 "American Bicentennial, the Pentagon began offering guided tours to the general public. Tours were suspended after the "September 11, 2001 attacks, but are currently available to the general public with reservations 14–90 days in advance.
The Pentagon and its parking lots are used as a staging area for a number of large events, including the "Army Ten-Miler, the "Marine Corps Marathon and "Rolling Thunder motorcycle ride. In 2005, the Department of Defense organized the "America Supports Your Freedom Walk" in the parking lot, an event held to show solidarity with the department's current and former employees.
The roads of the Pentagon Reservation are used daily by thousands of commuters between Arlington, Virginia and Washington, DC.
The Pentagon was listed on the "National Register of Historic Places in 1989, and was designated a "National Historic Landmark in 1992.
- "Supreme Headquarters Allied Powers Europe—Structure with similar purposes for "NATO.
- "Main Building of the Ministry of Defense, Russian equivalent
- "HaKirya, the "Israel Defense Forces Headquarters
- "List of National Historic Landmarks in Virginia
- "National Register of Historic Places listings in Arlington County, Virginia
- Federal Reserve Bank of Minneapolis Community Development Project. "Consumer Price Index (estimate) 1800–". Federal Reserve Bank of Minneapolis. Retrieved January 2, 2017.
- "National Park Service (2010-07-09). "National Register Information System". National Register of Historic Places. National Park Service.
- "Virginia Landmarks Register". Virginia Department of Historic Resources. Retrieved May 12, 2013.
- Steve Vogel, The Pentagon: a History (2003).
- "The Pentagon – George Bergstrom – Great Buildings Online". Greatbuildings.com. Retrieved October 26, 2008.
- The Pentagon, Facts & Figures (accessed August 23, 2014)
- "Pentagon Hot Dog Stand, Cold War Legend, to be Torn Down". United States Department of Defense. September 20, 2006. Retrieved May 6, 2010.
'It's rumored that a portion of their (Soviet) nuclear arsenal was directed at that building, the Pentagon hot dog stand,' tour guides tell visitors as they pass the stand. 'This is where the building earned the nickname Cafe Ground Zero, the deadliest hot dog stand in the world.'
- "Pentagon Memorial Dedication". DefenseLink.mil. Retrieved May 27, 2009.
- Goldberg (1992), p. 6–9
- "Intro – Secretaries of War and Secretaries of the Army". "United States Army Center of Military History. 1992.
- "Main Navy & Munitions Buildings". "Naval History & Heritage Command. Retrieved October 17, 2008.["dead link]
- Vogel (2007), pp. 29–33
- Vogel (2007), pp. 35–37
- Bureau of Public Roads memorandum, October 25, 1960.
- "General Information". Archived from the original on November 29, 2005. Retrieved December 4, 2005.
- Vogel, Steve (May 27, 2007). "How the Pentagon Got Its Shape". Washington Post. pp. W16. Retrieved May 26, 2007.
- Roig-Franzia, Manuel (May 13, 2010). "Hemp fans look toward Lyster Dewey's past, and the Pentagon, for higher ground". The Washington Post. Retrieved May 25, 2010.
- Goldberg (1992), p. 22
- Goldberg (1992), p. 33
- Goldberg (1992), p. 29
- Goldberg (1992), p. 34
- Vogel (2007), p. 131
- Goldberg (1992), p. 35; p. 44
- "Rare, Unseen: Building the Pentagon". LIFE.com.
- McGrath, Amanda (May 26, 2007). "How The Pentagon Got Its Shape (Gallery)". The Washington Post.
- Goldberg (1992), p. 52–53
- Owens, Jim (February 2005). "Replacing the stone and rebuilding the Pentagon". Mining Engineering. 57 (2): 21–26.
- Goldberg (1992), p. 39–42
- Goldberg, p. 36
- Weyeneth, Robert R. (2005). The Architecture of Racial Segregation: The Challenges of Preserving the Problematical Past. pp. 28–30.
- Carroll, James (2006). House of War: the Pentagon and the disastrous rise of American power (Print). Boston: Houghton Mifflin Co. pp. 4–5.
- Goldberg (1992), p. 47; p. 52
- Facts & Figures: Land Area and Cost
- White, Jean M. (February 16, 1967). "2500 Women Storm Pentagon Over War". Washington Post.
- Auerbach, Stuart (May 13, 1967). "Pentagon Protesters Jailed". Washington Post.
- "Flowers, Guns and an Iconic Snapshot". The Washington Post. March 18, 2007. Retrieved May 25, 2010.
- Jacobs, Ron (1997). The Way the Wind Blew. Verso. p. 142. "ISBN "1-85984-167-8.
- "8 Years After Start of War, Anger Reigns," Washington Post, March 17, 2007 page A1
- Vogel, Steve (June 22, 2011). "New Pentagon Is A Paragon". "Washington Post. p. 1.
- Renovation of the Pentagon. Retrieved October 9, 2006. Archived October 4, 2006, at the "Wayback Machine.
- "Flight 77, Video 2". Judicial Watch. Archived from the original on November 16, 2006.
- Isikoff, Michael; Daniel Klaidman (June 10, 2002). "The Hijackers We Let Escape". Newsweek. Retrieved October 22, 2009.
- Schrader, Esther (September 16, 2001). "Pentagon, a Vulnerable Building, Was Hit in Least Vulnerable Spot". Los Angeles Times. Retrieved Feb 25, 2010.
- "The Pentagon". globalsecurity.org. Retrieved February 25, 2010.
- "Where The Pentagon Was Hit". LA Times. Retrieved June 21, 2015.
- "Pentagon Renovation Program". Archived from the original on May 8, 2006. Retrieved December 4, 2005.["dead link]
- Childs, Nick (August 15, 2002). "Americas: Pentagon staff reclaim destroyed offices". BBC News. Retrieved December 4, 2005.
- "Pentagon History – September 11, 2001". Pentagon.osd.mil. Retrieved October 26, 2008.
- Pentagon Memorial Web site Archived January 9, 2009, at the "Wayback Machine.
- Official press release at the United States Department of Defense Archived May 11, 2006, at the "Wayback Machine.
- Wilgoren, Debbie; Nick Miroff; Robin Shulman (September 11, 2008). "Pentagon Memorial Dedicated on 7th Anniversary of Attacks". The Washington Post. "The Washington Post Company. Retrieved September 11, 2008.
- Klein, Allison; Williams, Clarence; Weil, Martin (March 5, 2010). "at Pentagon entrance leaves 2 police officers hurt, lone gunman dead". The Washington Post. p. A1.
- Christy Goodman and Maria Glod (October 20, 2010). "Gunman sought in Pentagon shooting". Washington Post. p. B1.
- Fox News article—Magnitude 5.9 Earthquake Hits Virginia, Sends Shockwaves Throughout East Coast (accessed August 23, 2011)
- US Capitol, Pentagon, State Department Shaken By 5.9 Magnitude Earthquake, Amy Bingham, ABC News at the "Wayback Machine (archived November 13, 2013)["dead link]
- Goldberg (1992), p. 57
- "How to Find a Room in the Pentagon". Headquarters, Dept. of the Army. Retrieved September 13, 2007.
- "Man shoots 2 officers outside Pentagon". CNN. March 5, 2010. Retrieved May 25, 2010.
- "Mixing Bowl Interchange Complex". roadstothefuture.com. Retrieved November 22, 2006.
- Facts & Figures: Zip Codes
- "Department of the Army (July 1, 2002). "Section 578.4 Medal of Honor". "Code of Federal Regulations Title 32, Volume 2. "Government Printing Office. Retrieved March 14, 2012.
- DoD Award Manual, November 23, 2010, 1348. 33, P. 31, 8. c. (1) (a)
- Tucker, Spencer C.; Arnold, James; Wiener, Roberta (2011). The Encyclopedia of North American Indian Wars, 1607–1890: A Political, Social, and Military History. ABC-CLIO. p. 879. "ISBN "978-1-85109-697-8. Retrieved March 14, 2012.
- The Congressional Medal of Honor Society is so designated because that was the name it was given in an act of Congress that was signed into law by "US President Dwight D. Eisenhower on August 5, 1958 as "Title 36, Chapter 33 of the U.S. Code (see "The Congressional Medal of Honor Society's History". Official Site. Congressional Medal of Honor Society. Retrieved October 1, 2006.). The law authorizing the society has since been transferred to Title 36, Chapter 405 of the U.S. Code. 
- "Welcome to the Headquarters Department of Defense: Self Guided Tour Brochure – Pentagon Tours Program". Retrieved December 2, 2013 
- Baker, Henderson "Inside the Pentagon Post 9/11" Scholastic News Online. Retrieved December 2, 2013 
- Maffre, John (May 15, 1968) "The President Looks to Peace 'For Which These Men...Have Fought...'" The Washington Post, page 1.
- Johnson, Lyndon B. (May 14, 1968) "Remarks Upon Dedicating the Hall of Heroes and Presenting the Medal of Honor to a Member of Each of the Nation's Military Services", The American Presidency Project. Retrieved November 30, 2013 
- Hughes, Libby (1992) Norman Schwartzkopf: Hero with a Heart Lincoln, Nebraska: IUniverse Publishing, page 109
- Hirschfelder, Paulette (2012) The Extraordinary Book of Native American Lists Lanham, Maryland: Scarecrow Press, page 220
- Roth, S. (June 23, 2000) "Pentagon's hall of heroes welcomes asian-american veterans". Gannett News Service. Retrieved December 1, 2013 
- Staff writer, (March 30, 1991) "Pentagon's gulf war spokesman retires". St.Petersburg Times. Retrieved on December 1, 2013 
- Omicinski, J. (December 1, 1999) "Comanche code-talkers honored for WWII service". Gannett News Service. Retrieved on December 3, 2013 
- Staff writer (February 26, 2004) "Readiness award". The Charleston Gazette. Retrieved on December 2, 2013 
- "Concessions – The Pentagon". Office of the Assistant Secretary of Defense for Public Affairs. Retrieved March 30, 2008.
- "Pentagon Gets New KFC/Pizza Hut/Taco Bell Multibranded Restaurant". AllBusiness. August 13, 2003. Archived from the original on February 6, 2008.
- "Center Courtyard Cafe" (PDF). Pentagon Renovator Newsletter. February 2008. Archived from the original (PDF) on April 9, 2008.
- Pentagon Renovation Program Archived October 13, 2007, at the "Wayback Machine.
- Pentagon Meditation and Prayer Room—website of the Pentagon Meditation Club:
- Pentagon Memorial Chapel place to grieve, reflect, heal army.mil
- Halloran, Richard (April 18, 1982). "Penetrating the Pentagon". The New York Times. pp. Section 10, page 39.
- "Frommer's: The Pentagon". Retrieved December 1, 2015.
- "Tour Guidelines". Retrieved December 1, 2015.
- Neuman, Johanna (September 11, 2005). "Pentagon's 'Freedom Walk' Is a March Along America's Divide". Los Angeles Times. Retrieved October 20, 2010.
- Carroll, James (2007). House of War: The Pentagon and the Disastrous Rise of American Power. Mariner Books. "ISBN "0-618-18780-4.
- Goldberg, Alfred (1992). The Pentagon: The First Fifty Years. Office of the Secretary of Defense / Government Printing Office. "ISBN "0-16-037979-2.
- Vogel, Steve (2007). The Pentagon – A History: The Untold Story of the Wartime Race to Build the Pentagon and to Restore it Sixty Years Later. Random House. "ISBN "0-8129-7325-9.
|""||Wikimedia Commons has media related to The Pentagon.|
- The Pentagon website
- Popular Mechanics, March 1943, "Army's Giant Five-by-Five" one of earliest World War II articles on the Pentagon
- Pentagon Force Protection Agency
- Pentagon Renovation Program
- The Worldwide Network of US Military Bases
- The Pentagon: Relocation Information and The Pentagon Q&A
- Great Buildings Online – The Pentagon
- How the Pentagon Got Its Shape – The Washington Post, May 26, 2007
- A House Divided: Pentagon Trivia Fact retrieved June 13, 2008.
- Satellite image from Mapygon
- The Construction of The Pentagon—Somervell's Folly