it is a sled and they call it skeleton

Skeleton is a winter sport in which competitors aim to drive a one-person sled in a prone, head-first position down an ice track in the fastest time. This differs from luge, where the rider drives the sled from a supine, feet-first orientation. Top speeds attained in skeleton—approximately 130 km/h (80 mph)—are slightly slower than in luge. This Olympic sport is known in some parts of the world as tobogganing. It takes its name from the stripped-down sled, which originally was a bare frame, like a skeleton. There is also a theory about the name that it is a mispronunciation of the Norwegian word 'kjelke' which signifies sled or luge.

Skeleton is the oldest competitive sledding sport. It originates from St. Moritz, Switzerland, where in 1884 the Cresta run was built by Major Bulpetts. When the Winter Olympic Games were held there in 1928 & 1948, the event was included in the program. Skeleton was added to the Olympic program beginning with the 2002 Games.