A crow’s nest is a structure in the upper part of the main mast of a ship used as a lookout point. This position ensured the best view for lookouts to spot approaching hazards, other ships, or land. It was the best device for this purpose until the invention of the first working radar system in 1935. In the early 19th century, it was simply a barrel or a basket lashed to the tallest mast. Later, it became a specially designed platform with protective railing.
The crow’s nest on a ship was named thus because crows were often taken on board to help the navigator determine where the closest land lay. In cases of poor visibility a crow was released and the navigator plotted a course that matched the bird’s because it invariably headed towards land, ‘as the crow flies’. The crows’ cages were kept high in the main mast where the look-out stood watch.