Durlston Castle stands within Durlston Country Park, a 1.13 square-kilometre country park and nature reserve stretching along the coastline south of Swanage, on the Isle of Purbeck in Dorset.
Wikipedia https://en.wikipedia.org/wiki/Durlston_Castle
Address (Unnamed Road), BH19 2, United Kingdom
Coordinates 50°35'42.394" N -1°57'10.931" E