Nautical mile Nautical mile A nautical mile (also known as an air mile) is a unit of measurement defined as exactly . Historically, it was defined as one minute of latitude, which is one sixtieth of a degree of latitude – i.e. since a minute of a degree is x = , the Earth's polar circumference is approximately 21,600 nautical miles. It is a non-SI unit which today has a continued use in both air and marine navigation, and for the definition of territorial waters. There is no single internationally agreed symbol. While using M itself, the International Bureau of Weights and
Adlard Coles Nautical Adlard Coles Nautical Adlard Coles Nautical is a nautical publisher, with over 300 books in print. The company publishes books on topics of interest to sailors and motorboaters and also ‘landlubbers’ with an interest in the sea. Their list includes almanacs, cruising guides, pilot books and how-to instruction books, as well as large format photographic books, sailing narratives and sea-related reference, maritime history, humour and trivia books. Adlard Coles Nautical has been part of Bloomsbury Publishing since 2003. The company was founded by yachtsman Kaines Adlard Coles in 1947. He wrote many of the books, including pilots, sailing narratives and