Concierge.com's insider take:
Stretching almost 4,000 miles across northern China, the Great Wall of China was a 1,800-year construction project designed to keep out invading Mongolian warriors. Begun during the Qin dynasty in 200 B.C., the wall has inspired many myths—and for the record, it is not visible from space, nor is it a continuous structure. Several sections are easily accessible from Beijing. The most famous, and consequently overrun, is Badaling, an hour's drive northwest of the city. The location makes it ideal for a whistle-stop tour, and you'll get a window into the Chinese tourism machine (take a gondola up one side and a roller coaster down the other to a market jam-packed with stalls, all selling identical T-shirts). To dodge the worst of the crowds, avoid weekends and arrive in the early morning or late afternoon.
About an hour northeast of the city, the Mutianyu section of the Great Wall has expansive scenery, fewer tourists, and a cable car for quick trips up and down. A bit farther afield (about three hours northeast of the city), fit types can take the four-hour hike between the "wild wall" sections of Simatai and Jinshanling, which are indeed overgrown and semi-ruined, but beautiful. Most Beijing hotels can arrange day trips to the Great Wall, but visitors who prefer to take their time exploring should consider staying nearby, at the Commune by the Great Wall Kempinski or the Red Capital Ranch. More intrepid types can book a guide for an overnight hike and either camp atop one of the crumbling watchtowers or stay with a family in a nearby farmhouse. Cycle China arranges private guides for overnight trips.