The most important contributors to a roller coaster's ability to instill fear in its patrons are its speed and height. The minds behind the Kingda Ka at Six Flags Great Adventure in Jackson, New Jersey clearly understood this, as they combined speed and height to create the scariest roller coaster in the world.

Takabisha (高飛車) is a Gerstlauer Euro-Fighter steel roller coaster located at Fuji-Q Highland in Fujiyoshida, Yamanashi, Japan. It opened on 16 July 2011, and is known for having a drop angle of 121°.

The Steel Dragon 2000 is the longest roller coaster in the world, measuring a whopping 8,133 feet in length.

For the Formula Rossa, the G-Force - in other words, its acceleration relative to free-fall - is 1.7Gs. "Everybody knows that it is a scary experience - but it is a safe experience," Prof Minetti says.