Rosemary Bank is a seamount approximately 120 kilometres west of Scotland, located in the Rockall Trough, in the northeast Atlantic. It was discovered in 1930 by the survey vessel HMS Rosemary, from which it takes its name.
The feature originated about 70 million years ago, as a result of volcanic activity. Rosemary Bank rises to approximately 2000 metres, its highest point being 300 metres below sea-level. The sea bed immediately surrounding it is approximately 2300 metres below sea-level. Around its base lies a thin "moat", where the sea-bottom is at a lower depth than the surrounding terrain.
References
Rosemary Bank Wikipedia(Text) CC BY-SA