Allegan County is a county in the U.S. state of Michigan. As of 2010 census, the population was 111,408. The county seat is Allegan. The name was coined by Henry Rowe Schoolcraft to sound like a Native American word.
Allegan County is primarily an agricultural area that is rapidly becoming urbanized as the population centers of Grand Rapids on the northeast and Kalamazoo to the southeast expand into Allegan County. A portion of the city of Holland lies within the northwest portion of the county, as does a larger urbanized area around it. In the southwest corner, a small portion of the city of South Haven extends into Allegan County. The Lake Michigan shoreline has long been a popular place for vacation homes, and that such development continues, especially around Saugatuck and Douglas.
The largest city wholly within the county is Allegan, the county seat.
The county has long been a regional tourist draw, particularly the Tulip Time Festival in Holland and the area along Lake Michigan. Another draw is Allegan State Game Area, a forest attracting campers, snowmobilers, cross-country skiers and hunters. Allegan County also hosts Saugatuck Dunes State Park with trails through scenic dunes and a swimming beach on Lake Michigan. Lake Allegan is another popular destination.