A dog sled is a sled that is pulled by sled dogs and can go over ice and snow. Dog sleds were first made by First Nations people in Canada before the English and French got there, because they had no horses so they used dogs to travel. They were also made by people in Norway, Sweden, Finland and Russia because it was also easier to travel with dogs in parts of those countries.
Racing dog sleds is a popular sport which a lot of people enjoy watching or actually going in the sleds to race. It is more popular in places where there is not much horse racing.