Sark consists of two main parts, Greater Sark, located at about 49° 25' N x 2° 22' W, and Little Sark to the south. They are connected by a narrow isthmus called La Coupée which is 90 metres (300 ft) long and has a drop of 100 metres (330 ft) on each side. Protective railings were erected in 1900; before then, children would crawl across on their hands and knees to avoid being blown over the edge.
The highest point on Sark is 114 metres (374 ft) above sea-level. A windmill, dated 1571, is found there, the sails of which were removed during World War I. This high point is named Le Moulin, after the windmill. The location is also the highest point in the Bailiwick of Guernsey. Little Sark had a number of mines accessing a source of galena. At Port Gorey, the ruins of silver mines may be seen. Off the south end of Little Sark are the Venus Pool and the Adonis Pool, both natural swimming pools whose waters are refreshed at high tide.
The whole island is extensively penetrated at sea level by natural cave formations, some of which are only safely accessible at low tide.
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