Washington D.C.

Washington D.C. needs 3 days: the National Mall with its Smithsonian museums (free admission) on one, the Capitol and the White House on another, and the presidential memorials on the third. March-May coincides with cherry blossom season, the city's most photographed event. It's among the country's priciest cities for lodging, though the main museums and monuments are free, which balances the budget. It's the political capital of the United States, home to all three branches of the federal government, with neoclassical architecture deliberately designed to project the grandeur of a young nation.