The Five-Sided Puzzle Palace
A man lived there secretly? Stunning facts about the Pentagon
Image: Touch Of Light, CC BY-SA 4.0, via Wikimedia Commons
Did you know that construction on the Pentagon building began on September 11, 1941, exactly 60 years before it was attacked? The home of the US Department of Defense has stood for more than 80 years. Although its iconic shape is intriguing in itself, it hides deeper secrets that many Americans have never heard of. Did you know it feeds 26,000 people a day—at a McDonald's, a Five Guys, a Taco Bell, and over 30 other restaurants? Or that a man secretly lived inside its walls for years? Let’s dive into the Pentagon building’s secrets.
1
A renovation project saved thousands of lives on 9/11
On September 11, 2001, American Airlines Flight 77 struck the Pentagon at 9:37 a.m., killing 189 people. Few people know this part: the death toll could have been much higher. But there was a renovation project underway at the time of the attacks.
The Pentagon’s five-sided structure is divided into five "wedges," and workers had been renovating them one at a time. Flight 77 struck the wedge that had just been completed. Of the 4,500 people who normally worked in that section, only about 800 had moved back in. Without the reinforced construction and the incomplete occupancy, experts believe the casualties would have been catastrophically higher.
2
The Cold War and the hot dog stand
In the middle of the Pentagon’s five-acre center courtyard once stood a modest hot dog stand. According to a Cold War legend (one still retold by official Pentagon tour guides on every public tour), between the 60s and the 80s, Soviet satellite images tracked large groups of high-ranking military officials converging on that small building at the same time every day.
Soviet intelligence reportedly concluded the structure must be the entrance to some underground bunker in America. In reality, all it did was sell lunch. In 2006, the original stand was torn down, and a sandwich shop was built in its place.
3
Its construction began on September 11th, exactly 60 years before the attack
Builders broke ground on the Pentagon on September 11, 1941. That was exactly 60 years to the day before the September 11, 2001, terrorist attacks that would strike the same building.
Construction had been ordered by Army Brigadier General Brehon Somervell, who wanted a permanent headquarters for the Defense Department to replace its then-17 scattered offices across Washington, D.C.
The project was extraordinarily ambitious: plans called for the world’s largest office building to be completed in just 16 months. In the end, the conception, design, and construction of the entire Pentagon building took a total of 15 months.
4
The same person oversaw its construction and the Manhattan Project
Colonel Leslie Groves of the Army Corps of Engineers took charge of Pentagon construction in August 1941. He worked six days a week and drove his team relentlessly, at one point employing more than 15,000 workers around the clock.
When the Pentagon was finished in January 1943, Groves was assigned to lead the Manhattan Project, America’s secret program to build the atomic bomb . His deputy, Captain Robert Furman, followed him into the Manhattan Project as chief of foreign intelligence. Together, the men who built the world’s largest office building went on to produce the weapon that ended World War II.
5
Why is it shaped like that?
The Pentagon’s iconic five-sided shape was the consequence of a geographic accident. The original site selected for the building, near Arlington Cemetery, **happened to be bordered on five sides by roads. **Architects designed the structure to fit those boundaries, producing a pentagonal floor plan. Then President Franklin D. Roosevelt intervened: worried the massive building would obstruct the view of Washington, D.C. from Arlington, he ordered the site moved to its current location along the Potomac River. But the five-sided design had already been drawn up, and nobody changed it.
6
It was the first desegregated building in Virginia
When the Pentagon was designed in 1941, segregation was the law in Virginia. Original plans called for doubled bathroom facilities: separate ones for Black and white employees, as required by Virginia statute. But President Roosevelt had signed Executive Order 8802 in June 1941, prohibiting racial discrimination in federal employment and government contracting.
As a federal building, the Pentagon was exempt from Virginia law. It became the only building in the state where segregation was not enforced. A fully desegregated federal workplace that opened in 1943. The doubled bathrooms were built anyway, as the plans were too far along to revise, but were never used as separately designated spaces.
7
Its construction was surprisingly frugal and incredibly fast
Ground broke on September 11, 1941, and construction finished on January 15, 1943, just 16 months later. More than 15,000 workers were on site around the clock. Wartime office shortages were so severe that employees moved into completed wings before the rest of the building was finished. Steel was too scarce to use extensively, so builders relied almost entirely on reinforced concrete. The 689,000 tons of sand and gravel required came directly from the nearby Potomac River, cutting transportation costs. The project was budgeted at $35 million, but the final bill was $63 million, which would translate to over $900 million in today’s dollars.
8
You can walk between its farthest points in only 7 minutes
The Pentagon is the world’s largest low-rise office building: 6.5 million square feet of space, which is three times the total floor area of the Empire State Building. Each of its five outer walls is 921 feet long. It has 7,754 windows and 17.5 miles of corridors. Approximately 26,000 military and civilian employees report for work there every day.
Despite that scale, the building’s concentric ring design is so efficient that it takes only about seven minutes to walk between its two farthest points.
9
The man who secretly lived inside its walls
During construction, Colonel Groves drove his deputy, Captain Robert Furman, so relentlessly that Furman rarely left the building. To cope, Furman had contractors build him a small, windowless apartment hidden inside the walls of the Army’s Ordnance Division. In this private room, he could sleep and shower without leaving the premises.
When construction ended and personnel dispersed, knowledge of the hidden room was never passed on to building management. Months later, when Furman returned to Washington on Manhattan Project intelligence business, he found the apartment undiscovered and exactly as he’d left it.
For over a year, he would slip back to the Pentagon, pop open a wall panel, spend the night, and emerge in the morning with his suitcase. He was finally caught in 1943 and forced to surrender the keys. It was never disclosed whether the secret apartment was maintained or eventually absorbed back into the official floor plans.
10
It houses over 30 restaurants, including everyone's favorite chains
The Pentagon feeds roughly 26,000 people a day, and its dining options read less like a military headquarters and more like a mall food court. The main Concourse Food Court, which opened in September 2009 and seats 875 people, is the largest of several dining areas.
Confirmed chains currently inside the building include McDonald’s, Five Guys, Subway, Popeyes, Starbucks (multiple locations), Dunkin’ (two locations), Panera Bread, Taco Bell, Panda Express, Baskin-Robbins, Potbelly, Jamba Juice, and Moe’s Southwest Grill, among others. The building also houses a CVS pharmacy, a florist, a jeweler, and a dry cleaner. In the summer of 2024, Potbelly became the first restaurant to open in the center courtyard. Yes, the very spot where the legendary Cold War hot dog stand once stood.
