When Japanese forces bombed Pearl Harbor on December 7, 1941, the Secret Service realized something unsettling: If the White House were the target of a similar attack, the soft sandstone structure would easily crumble, and they had no plan of action for ferrying President Franklin D. Roosevelt to safety.

Within weeks, construction had begun on two subterranean projects. The first was a tunnel that connected the East Wing of the White House to the nearby (and much sturdier) Treasury Building, a granite stronghold with underground bank vaults. According to Robert Klara’s book The Hidden White House, one or more of those vaults was transformed into an 1100-square-foot shelter with 10 rooms, including a bedroom, a well-stocked kitchen, a cozy leather chair, and plenty of plush carpeting. The other was a smaller bunker below the East Wing itself. At just 40 feet by 40 feet, the two-room suite featured 7-foot-thick concrete walls, a medical room, enough food and water to sustain dozens of people for days, and a diesel-generated power system.

During President Harry S. Truman’s massive renovation of the White House between 1948 and 1952, this bunker was expanded into what’s now known as the Presidential Emergency Operations Center (PEOC). As Gizmodo reports, it was there that the Secret Service escorted Vice President Dick Cheney and his wife, Lynne; National Security Advisor Condoleezza Rice; First Lady Laura Bush; and other senior officials during the attacks on September 11, 2001.

Vice President Dick Cheney in the PEOC on 9/11.The U.S. National Archives, Flickr // No Known Copyright Restrictions

While the dimensions and layout of the entire space are kept under wraps, we do know a little about it from photos taken at the time, which show a plain room with television screens, a long conference table, and the Seal of the President of the United States hung on one wall. Laura Bush revealed a few more details in her 2010 memoir, Spoken From the Heart:

“I was hustled inside and downstairs through a pair of big steel doors that closed behind me with a loud hiss, forming an airtight seal … We walked along old tile floors with pipes hanging from the ceiling and all kinds of mechanical equipment. The PEOC is designed to be a command center during emergencies, with televisions, phones, and communications facilities.”

When President George Bush, who had been in Florida that day, arrived at the bunker just after 7 p.m., the Secret Service suggested he and Laura spend the night in the PEOC. “They showed us the bed, a fold-out that looked like it had been installed when FDR was president,” Laura wrote. “George and I stared at it, and we both said no.”

In 2010, workers broke ground on the North Lawn of the White House for yet another underground project. According to the Washington Examiner, the official word was that they were updating electrical wiring and air conditioning in the building, but some journalists speculated this was just to cover for the construction of a new White House bunker. In his 2018 book The Trump White House: Changing the Rules of the Game, former Washington Post journalist Ronald Kessler confirmed this theory.

Kessler alleged the highly secret structure was “at least five stories deep” and could “house the staff of the entire West Wing indefinitely in the event of a weapons of mass destruction attack.” It even has its own air supply, so occupants would be safe from nuclear radiation. Earlier this week, he explained to The Washington Post that the impetus for creating this new bunker was the realization during 9/11 that it wouldn't be feasible to transport White House officials to an existing offsite shelter if the nation were under attack in the future—traffic would make leaving the city by car too time-consuming, and air travel would likely be too dangerous.

And, though Kessler didn’t comment on the furniture, it’s probably safe to assume this state-of-the-art shelter features something more comfortable than a few fold-out beds from the 1940s.

[h/t Gizmodo]