Spartanburg Police spokesman Art Littlejohn says more than a dozen children and adults were taken to the hospital.
The county runs Cleveland Park. Spartanburg County Councilman David Britt says the train was inspected Wednesday and went on several test runs before Saturday, its first day of operation for the season.
He told the Herald-Journal of Spartanburg that the train's track, which collapsed in the crash, had been reworked a couple of years ago.
The derailment is under investigation.