The tilting building in South Korea
13 May 2014 Last updated at 08:31 BST
Construction workers in South Korea got a shock when one of the buildings suddenly started to tilt to one side.
The building is still being built and no one knows what caused it.
The twenty degree angle it's tilting at is five times greater than that of Italy's famous landmark, the leaning tower of Pisa.
No-one was hurt in the incident.