Euthanasia Coaster

The Euthanasia Coaster is an art concept. The idea was a steel roller coaster designed to kill its passengers. 
In 2010, it was designed and made into a scale model by Julijonas Urbonas. Urbonas used to work in an amusement park. Urbonas said that the goal of his proposed roller coaster is to take lives "with elegance and euphoria". Urbonas said it would be like "euthanasia" or "execution". 
John Allen, who was the president of the Philadelphia Toboggan Company, gave Urbonas the idea. Allen wanted an "ultimate" roller coaster that "sends out 24 people and they all come back dead". Urbonas took Allen's idea and designed the roller coaster. Urbonas said the roller coaster would make its passengers unconscious before killing them. It was criticized by the anti-euthanasia association Care Not Killing.
The roller coaster kills its passengers by drastically decreasing oxygen in their brains.