This year will see the 10th anniversary of the Green Dragon, the unique roller coaster at GreenWood Forest Park in North Wales, UK.

Built in early 2004, the Green Dragon is the only roller coaster of its kind in the world. The ride combines traditional roller coasters with funicular technology that was developed and used 200 years ago in the slate quarries of North Wales.

Stephen Bristow, GreenWood Forest Park's managing director, said: "Once it starts, the ride itself is gravity driven but it is at the very beginning where we turn people power into the energy we need.

"This energy is used to pull the coaster cars up to the starting point. Pulling the cars to the top of the ride is where the old slate quarry technology comes in.

Bristow added: "Having walked up the coaster hill, visitors enter a people carrier and travel down an incline. This descent, through the use of the slate quarry technology, pulls the cars up to the station. Passengers then leave the carrier and walk up the hill a second time to the station where they enter the cars for the ride itself."

Since building the coaster, visitor numbers to GreenWood Forest Park have risen from 94,000 in 2003 to 135,000 in 2013.