1) South Dakota's largest industry is agriculture, producing crops like wheat, corn, and soybeans as well as livestock.
2) Bison once numbered over 60 million but were hunted to near extinction by the late 1800s, though conservation efforts have brought their numbers back up to around 250,000 today.
3) Gold was discovered in the Black Hills in 1874, sparking a mining boom that drew prospectors to towns like Deadwood and Lead.