HILL CITY, S.D.— The North American Railcar Operators Association is in Hill City for its annual railcar run. However, this annual run down the Black Hills line has become so popular it's attracted members from other states. Dave Voeltz with the North American Railcar Operators Association says, "Some of them are very nice. ADVERTISEMENT16 cars are participating in the trek from Hill City to Keystone. The railcar run has been taking place on the 1880 Tracks for around 20 years.