The Lanzhou sheepskin raft is the oldest and most primitive transportation vessel along the Yellow River. But being able to travel 200 km in a single day, it has been an important part of the Yellow River culture. 

The raft is as its name suggests made using sheepskins, which are made into bags, inflated and tied to a wooden frame. It emerged during the Southern Song Dynasty (1127-1279), and has a history of more than 1,900 years.