Assertion: amusement park's roller coaster | /r/CapableOf | appear beginning in 1960
Facets:
Source sentences:
text: In the 1940s and 1950s, several flat rides were added to the park, and in the 1960s, the first roller coasters appeared beginning with Mad Mouse in 1960 and the John C. Allen wooden roller coaster, the Cannon Ball, in 1967.