Just skateboarding down the side of a building...

Skateboarder Sandro Dias has set a new world record by riding down the side of a huge building.

The world champion rode a mega ramp built on the side of a 21-story building in Porto Alegre in Brazil.

Sandro had been testing the ramp over the past couple of weeks, starting higher and higher up the ramp until he final reached the record-breaking 70-metre mark.

He was also surrounded with an expert safety team to make sure nothing went wrong.

Take a look.