<P> The Broads National Park is a network of mostly navigable rivers and lakes in the English counties of Norfolk and Suffolk . The lakes, known as broads, were formed by the flooding of peat workings . The Broads, and some surrounding land, were constituted as a special area with a level of protection similar to a national park by the Norfolk and Suffolk Broads Act 1988 . The Broads Authority, a special statutory authority responsible for managing the area, became operational in 1989 . </P> <P> The area is 303 square kilometres (117 sq mi), most of which is in Norfolk, with over 200 kilometres (120 mi) of navigable waterways . There are seven rivers and 63 broads, mostly less than 4 metres (13 ft) deep . Thirteen broads are generally open to navigation, with a further three having navigable channels . Some broads have navigation restrictions imposed on them in autumn and winter, although the legality of the restrictions is questionable . </P>

When did the broads become a national park
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