One of the most important race tracks in North America, originally built in 1894, goes by what nickname in the horse racing industry?

Answer:These grassy areas were known as downs. Later, after real tracks were constructed (usually on the same sites) they named the track and kept the downs in the name. Probably the most famous track there was Epsom Downs which originated around 1661 and became famous for the big race they started known as "The Derby