Ontonagon County ( ) is a county in the Upper Peninsula of the U.S. state of Michigan. As of the 2020 census, the population was 5,816, making it Michigan's third-least populous county. The county seat is Ontonagon. The county was set off in 1843, and organized in 1848. It is also the westernmost county in the United States that lies within the Eastern Time Zone.

thumb|[[Lake of the Clouds in Porcupine Mountains Wilderness State Park]]

thumb|[[Agate Falls Scenic Site|Agate Falls]]

History

In 1843, Michigan's Upper Peninsula was divided into Mackinac, Chippewa, Marquette, Schoolcraft, Delta, and Ontonagon Counties. In 1845, a portion of Ontonagon County was partitioned to be part of Houghton County. In 1846, the village of Ontonagon was named as the county seat of Ontonagon County.

Ontonagon County is part of Copper Country, a region of the Upper Peninsula with prevalent copper mining from 1845 until the late 1960s. Prehistoric mining was conducted by local Native American populations. The first attempts by Europeans to mine copper in the area came in 1771 in the Ontonagon River. The Ontonagan Copper Boulder was removed from the west branch of the Ontonagon River and transported in 1842 to Detroit where it was weighed at 3708 pounds, thence to the Smithsonian Institution. The last copper mine in Copper Country was the White Pine mine, which closed in 1995.

Etymology

The county is named after the Ontonagon River. The name is said to be loosely derived from an Ojibwe language word noojitoon ziibi, meaning "hunting river." It is the third-largest county in Michigan by area.

Ontonagon County is located in the western Upper Peninsula, along the shore of Lake Superior. At a longitude of 89.5°W, it is the westernmost county in the United States contained entirely within the Eastern Time Zone.

Geographic features

  • Porcupine Mountains
  • Lake of the Clouds
  • Lake Superior
  • Lake Gogebic is the largest lake in the Upper Peninsula.
  • Corpse Pond
  • Ontonagon River
  • Firesteel River
  • Flintsteel River
  • Halfway Creek
  • Townline Creek
  • Maple Leaf Creek

Adjacent counties

By land

  • Houghton County (east)
  • Iron County (southeast; CST border)
  • Gogebic County (south, southwest; CST border)

By water

  • Ashland County, Wisconsin (west; CST border)
  • Cook County, Minnesota (northwest; CST border)
  • Keweenaw County (northeast)

National protected areas

  • Keweenaw National Historical Park (part)
  • Ottawa National Forest (part)

Transportation

Major highways

  • – runs north–south through east-central part of county. Enters south line from Watersmeet, passes Paulding, Bruce Crossing, and Rockland, ending at Ontonagon.
  • – enters east line of county at south of NE county corner. Runs SW, passing Mass City and Lake Mine, to intersection with M-38 east of Rockland.
  • – runs east–west thru southern part of county. Enters north of SE county corner. Runs westerly into Gogebic County.
  • – enters east line of county at a point east of Mass City. Runs west to Lake Mine, then WNW to terminus at Ontonagon.
  • – runs north–south through center part of county. Enters south line on west side of Lake Gogebic; runs north to Lake Superior shoreline. Runs NE along shoreline to terminus at Ontonagon.

Airport

  • link=|alt=|20x20px Ontonagon County Airport (KOGM) serves the county and surrounding communities.

Demographics