A riverboat is a watercraft designed for inland navigation on lakes, rivers, and artificial waterways. They are generally equipped and outfitted as work boats in one of the carrying trades, for freight or people transport, including luxury units constructed for entertainment enterprises, such as lake or harbour tour boats. As larger water craft, virtually all riverboats are especially designed and constructed, or alternatively, constructed with special purpose features that optimizes them as riverine or lake service craft—such as dredgers, survey boats, fisheries management craft, fireboats and law enforcement patrol craft.