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city, seat (1837) of Ottawa county, southwestern Michigan, U.S., located at the mouth of the Grand River, about 15 miles (25 km) south of Muskegon on the shore of Lake Michigan. A fur-trading post was built on the site in 1834; the village of Grand Haven was laid out the next year. With the construction of several sawmills on the river, it soon developed into an active centre for lumbering. Shipbuilding and fishing became important industries in the 1850s, and in 1858 the town became a ferry port on the Detroit and Milwaukee Railroad. The discovery in 1870 of mineral-rich springs in the area encouraged the city's growth as a resort. With the decline of the timber trade at the end of the 19th century, Grand Haven's economy came to rely on these newer economic activities, as well as on a growing fruit market. Its fine natural harbour handles shipments of sand, gravel, crushed limestone, coal, and petroleum; it is also used for commercial fishing and is the site of a U.S. Coast Guard base. The city's manufactures include auto parts, furniture, metal products, and industrial equipment.