As Eaglehawk Neck / Teralina forms a natural thin gateway between the peninsulas, it was used by the British as a place to stop convicts attempting to escape from Port Arthur and other penal institutions on the Tasman Peninsula. A system was developed where a line of dogs were chained to posts across the 'Neck' to warn of any convicts attempting to escape. The Dog Line was first implemented in 1831 and was used until the closure of Port Arthur in the 1870s.