Washington DC vs Yellowstone and Grand Teton

Washington DC may be the best family city in America, mostly because so much of it is free. In three days with kids you can stand under real spacecraft at the National Air and Space Museum, meet the Hope Diamond and towering dinosaur skeletons at the National Museum of Natural History, and see the original Star-Spangled Banner at the National Museum of American History, all without paying admission. Some sites use free timed-entry passes, so reserve them before you go. Between museums, let kids run on the grassy National Mall, ride the carousel and picnic with food-truck lunches. Save an evening for the monuments at sunset, when the Lincoln Memorial glows, the Reflecting Pool mirrors the Washington Monument and the crowds thin out. The Metro makes getting around easy, and younger children ride free with a paying adult. With more time, see giant pandas, elephants and great apes at the free National Zoo, tour the US Capitol and the stunning Library of Congress, crack codes at the International Spy Museum, and day-trip to George Washington's Mount Vernon and the brick sidewalks of Old Town Alexandria. Spring and fall are ideal, with cherry blossoms in late March to early April.

Yellowstone and Grand Teton sit side by side in northwest Wyoming, linked by a short parkway, and together they make one of the great American road trips. Yellowstone, the world's first national park, holds more than half the planet's active geysers, including Old Faithful, plus the rainbow-colored Grand Prismatic Spring, the thundering Lower Falls of the Grand Canyon of the Yellowstone and terraced hot springs at Mammoth. It is also the best place in the Lower 48 to see big wildlife: bison herds in Hayden and Lamar valleys, elk, pronghorn, bears and, with patience and a spotting scope, wolves. Just south, Grand Teton's jagged peaks rise straight out of the valley floor above Jackson Lake and Jenny Lake, with sunsets that rival anything in the West. Fly into Jackson Hole or Bozeman, rent a car and plan on long but rewarding drives. Neither park uses timed entry, but in-park lodging books up months ahead, parking at Old Faithful and Grand Prismatic fills by late morning, and most of Yellowstone's roads close to cars from early November to late April, so summer and early fall are the main seasons.