1. Hovenweep National Monument, Utah and Colorado
Mesa Verde National Park in Colorado gets the spotlight (and the crowds). That said, Hovenweep, straddling the Utah-Colorado border, is an amazing spot to delve into the history of the Ancestral Puebloans (aka the Anasazi), who called the American Southwest home a millennium ago.
2. Buffalo Bill Center of the West, Cody, Wyoming
Showcasing the life and times of William "Buffalo Bill" Cody — likely the most famous celebrity on the planet at his peak — this fantastic facility near Yellowstone National Park also has galleries dedicated to Native American history, the regional ecosystem and firearms. And don't miss the collection of Western art, one of the best anywhere.
3. Grand Central Station, New York
While hordes of tourists descend upon such overrated meccas as Times Square and South Street Seaport, you can get a very different slice of New York by wandering the open spaces, hallways, ramps and food courts of Grand Central Station, where tens of thousands of New Yorkers and local commuters pass through every day. Gaze up at its splendid "constellation" ceiling, have some fresh oysters at its famed Oyster Bar, nab a drink at the posh Campbell Apartment, or even shop for groceries at its gourmet food court — all while rubbing shoulders with locals speeding to or from their daily gigs.