The helicopter carrying Philip Calvert (Anthony Hopkins) flies past some very large caves while looking for sunken ships in When Eight Bells Toll. Filmed at Fingals Cave on the island of Staffa which lies to the south west of Mull. This cave is famous, amongst others reasons, for being the inspiration for the German composer Felix Mendelssohn to write part of his Hebrides Overture between 1830 and 1832.