It's amazing when you think about it: This house has served as a residence, office, reception site, and world embassy for every U.S. president since John Adams. The White House is the only private residence of a head of state that has opened its doors to the public for tours, free of charge. It was Thomas Jefferson who started this practice, which is stopped only during wartime. Our war on terrorism caused the administration in 2002 to close the White House for public tours for about 2 years. Thankfully, the White House is once again open for public tours, though not walkup tours. An Act of Congress in 1790 established the city, now known as Washington, District of Columbia, as the seat of the federal government. George Washington and city planner Pierre L'Enfant chose the site for the White House (or "President's House," as it was called before whitewashing brought the name "White House" into use) and staged a contest to find a builder. Although Washington picked the winner -- Irishman James Hoban -- he was the only president never to live in the White House. The structure took 8 years to build, starting in 1792, when its cornerstone was laid, and its facade is made of the same stone that was used to construct the Capitol. In 1814, during the War of 1812, the British set fire to the White House, gutting the interior; the exterior managed to endure only because a rainstorm extinguished the fire. What you see today is Hoban's basic creation: a building modeled after an Irish country house (in fact, Hoban had in mind the house of the Duke of Leinster in Dublin).Alterations over the years have incorporated the South Portico in 1824, the North Portico in 1829, and electricity in 1891, during Benjamin Harrison's presidency. In 1902, repairs and refurnishings of the White House cost nearly $500,000. No other great change took place until Harry Truman's presidency, when the interior was completely renovated, after the leg of Margaret Truman's piano cut through the dining room ceiling. The Trumans lived at Blair House across the street for nearly 4 years while the White House interior was shored up with steel girders and concrete. It's as solid as Gibraltar now.In 1961, Jacqueline Kennedy formed a Fine Arts Committee to help restore the famous rooms to their original grandeur, ensuring treatment of the White House as a museum of American history and decorative arts. "It just seemed to me such a shame when we came here to find hardly anything of the past in the house, hardly anything before 1902," Mrs. Kennedy observed. Presidents through the years have put their own stamp on the White House, one recent example being President George W. Bush's addition of the T-ball field to the South Lawn.Highlights of the tour include the Gold-and-White East Room, the scene of presidential receptions, weddings (Lynda Bird Johnson, for one), and other dazzling events. This is where the president entertains visiting heads of state and the place where seven of the eight presidents who died in office (all but Garfield) laid in state. It was also where Nixon resigned. The room's early-18th-century style was adopted during the Theodore Roosevelt renovation of 1902; it has parquet Fontainebleau oak floors and white-painted wood walls with fluted pilasters and classical relief inserts. Note the famous Gilbert Stuart portrait of George Washington that Dolley Madison saved from the British torch during the War of 1812. The portrait is the only object to have remained continuously in the White House since 1800 (except during times of reconstruction).You'll visit the Green Room, which was Thomas Jefferson's dining room but today is used as a sitting room. Mrs. Kennedy chose the green watered-silk-fabric wall covering. In the Oval Blue Room, decorated in the French Empire style chosen by James Monroe in 1817, presidents and first ladies have officially received guests since the Jefferson administration. It was, however, Van Buren's decor that began the "blue room" tradition. The walls, on which hang portraits of five presidents (including Rembrandt Peale's portrait of Thomas Jefferson and G. P. A. Healy's of Tyler), are covered in reproductions of early-19th-century French and American wallpaper. Grover Cleveland, the only president to wed in the White House, was married in the Blue Room. This room was also where the Reagans greeted the 52 Americans liberated after being held hostage in Iran for 444 days, and every year it's the setting for the White House Christmas tree.The Red Room, whose satin-covered walls and Empire furnishings are red, is used as a reception room, usually for afternoon teas. Several portraits of past presidents and a Gilbert Stuart portrait of Dolley Madison hang here. Dolley Madison used the Red Room for her famous Wednesday-night receptions.From the Red Room, you enter the State Dining Room. Modeled after late-18th-century neoclassical English houses, this room is a superb setting for state dinners and luncheons. Below G. P. A. Healy's portrait of Lincoln is an inscription written by John Adams on his second night in the White House (FDR had it carved into the mantel): "I Pray Heaven to Bestow The Best of Blessings on THIS HOUSE and on All that shall here-after Inhabit it. May none but Honest and Wise Men ever rule under this Roof."Note: Even if you have successfully reserved a White House tour for your group, you should still call tel. 202/456-7041 before setting out in the morning; in case the White House is closed on short notice because of unforeseen events. If this should happen to you, you should make a point of walking by the White House anyway, since its exterior is still pretty awe-inspiring. Stroll past it on Pennsylvania Avenue, down 15th Street past the Treasury Building, and along the backside and South Lawn, on E Street.