To find the cache, solve the following:
Assume N51, E000
CAMELOT
ALTON TOWERS
EFTELING
FRONTIER CITY - CAMELOT
DRAYTON MANOR + FRONTIER CITY
CANOBIE LAKE - DARIEN LAKE
CEDAR POINT - CANOBIE LAKE
CLEMENTON PARK - MAGIC SPRINGS
You can check you answer on Geochecker.