King's Trough King's Trough King's Trough is an undersea trough in the Atlantic Ocean. It is located on the east side of the Mid-Atlantic Ridge, northwest of the Açores-Biscay rise and roughly 400 km NNE of the Azores. It is about 400 km long, running in a NW–SE direction. To the east it branches into the Peake Deep and Freen Deep. The center depth is 4500 m. Surrounding the trough are high ridges and seamounts, such as the Antialtair seamount and the Crum seamount complex. Various explanations for the complex have been suggested, ranging from compression a former plate-boundary, transform faulting or
Rockall Basin (also known as the "Hatton Rockall Basin"). In 1956 the British scientist James Fisher referred to the island as "the most isolated small rock in the oceans of the world". The neighbouring Hasselwood Rock and several other pinnacles of the surrounding Helen's Reef are smaller, at half the size of Rockall or less, and equally remote, but those formations are legally not islands or points on land, as they are often submerged completely, only revealed momentarily above certain types of ocean surface waves. Rockall is about wide and long at its base and rises sheer to a height of