Because I prefer authentic travel experiences, I've hiked the Jinshanling to Simatai section of the Great Wall rather than the very touristy and totally restored Badaling section. Here's what you'll find:
1. It's a steep scramble, sometimes on all fours, on an often-dilapidated narrow stone path loaded with steps that are worn or missing entirely.
2. You'll have sweeping vistas that sometimes resemble a Chinese brush painting: misty forests, misty forested hills and lush valleys, and the ever-present serpentine wall with its multitude of towers.
3. You'll either be climbing up or down where you must carefully watch each and every step, because a misplaced foot could mean falling into a hole or off the Wall.
4. Watchtowers provide a bit of a welcome breeze and a pleasant respite from the blazing sun, especially if you hiking in the steamy, humid summer as I did. (It's better to trek here in the spring or fall.)
5. Bring plenty of water, snacks and lunch. And expect to spend about four to five hours hiking.
6. Take a cab to Jinshanling (it takes about 2-3 hours from Beijing, depending on traffic) and then arrange for your driver to pick you up in Simatai for the drive back to Beijing.
7. Along this six to seven mile trek, you'll pass some 30 towers on the way to Simatai. (If it's very hot, the towers -- at least those with a roof -- are great places for a picnic.)
8. The first and last parts are restored sections where it's easy to step into the multi-storied watchtowers and imagine the soldiers scanning the broad landscape, sending black smoke signals or lighting fires to alert others to an impending attack.
9. No matter the time of year, you won't find yourself alone on this section of the Wall, but not because of crowds. You'll be followed by a local vendor wearing casual attire, flimsy slippers and hefting a heavy bag loaded with bottled water, souvenir books, postcards, and T-shirts. They are quite persistent following you for miles, sometimes the whole way. So it's best to buy a bottle of water or another item from them. Many speak some English and can be quite helpful with directions and cautions on walking the Wall
10. In the final section on the way to Simatai, you'll have to cross a narrow suspension bridge over the Miyun Reservoir. (And both sections require an admission fee as does entrance to the bridge.)
11. Consider hiking the wall with this company: Wild Wall. William Lindesay guides hikes on various crumbled sections where you'll get an education on the Wall's history, architecture, natural landscape and myths.