Huanghuacheng Great Wall of China is about an hour and half drive north of Beijing.
This section of the wall when I visited is in a state of disrepair. Requires a walk across a dam that is about 75 feet (or higher) tall, about 3 feet wide. Then to get on the wall, you need to ascend a 25 foot bamboo ladder.
We didn't get on the wall itself, everyone decided in was not in the interest of our well being. But the views of the wall were pretty awesome.