I did that up by Heavenly Lake, which is about 1/3 in China and 2/3 in North Korea, back in 2001. The border was just a stone marker, a chain that ran to the cl

I did that up by Heavenly Lake, which is about 1/3 in China and 2/3 in North Korea, back in 2001. The border was just a stone marker, a chain that ran to the cliffside, and a very young (although about the same age as I was at the time), very bored member of the Chinese armed police. Apparently the North Korean guards were about a half mile back, so if you were unlucky enough to stumble all the way out to them you were well and truly screwed. I have a picture somewhere that a friend took when I jumped over the chain and turned around and smiled, two feet inside North Korea, before jumping back and smiling at the border guard, who pretty clearly just wanted to make sure no stupid American tourists got arrested by the Norks on his watch (apparently some European backpackers had tried to hike the perimeter of the lake not long before and spent a few months in a North Korean prison).