Coasterpedia:On this day/06 21
- 2014 - Ragin' Cajun, a Zamperla spinning wild mouse roller coaster opens at Six Flags America in Upper Marlboro, Maryland, United States.
- 1928 - Thunderbolt, a Bennett & Salisbury Company wooden roller coaster opens at Moxahala Amusement Park in Zanesville, Ohio, United States.