A girl in northern China was walking down the street talking on her cell phone recently ... when the sidewalk suddenly CAVED IN, and she fell about 15 feet.
A cab driver saw it happen and climbed down to help her. Apparently, she was unconscious when he got there. The fire department ended up having to use a ladder to get them both out, and a security camera caught it all on video.
Authorities say water had eroded the ground under the sidewalk and created a huge pit.