Volo Bog State Natural Area is the product of glaciers, like many other landscapes in northern & central Illinois. These massive sheets of ice smoothed till plains and carved gentle hills as they retreated north; they also created some of our lakes, one of which has filled in over the past several thousand years to become Volo Bog.
Read our history timeline to learn more about this incredible process and how people have always lived alongside Volo Bog.
Thank you to: those who archived historical Volo Bog materials; the Bess Bower Dunn Museum; and Tom Smith with the Brothertown Indian Nation for sharing about the history of Volo Bog & northeastern Illinois for this page.
A Brief Timeline
30,000 years ago. Much of Illinois is covered by a sheet of ice during the Wisconsin Glaciation, the most recent period of mass glaciation over North America. In some places this ice is half a mile thick. Illinois is home to now-extinct species such as saber-toothed tigers, ground sloths, and woolly mammoths.
12,000 years ago. Paleoindians inhabit northern Illinois. These people live in hunter-gatherer groups and probably travel seasonally to follow food sources.
10,000 years ago. As the glaciers retreat north, a chunk of ice breaks off and melts into a kettle-hole lake in northern Illinois. This lake is 50 acres across and 50 feet deep.
6,000 years ago. Stagnant, low-oxygen conditions in the lake limit decomposition, forming a bed of peat. This build-up of organic debris eventually fills in to create the acidic wetland that we today call Volo Bog.
Pre-colonial times. Algonquian peoples live throughout the Great Lakes region, including northeastern Illinois. Volo Bog's unique plants & animals are a great resource for people living nearby, such as the Potawatomi.
1833. The Treaty of Chicago forces Indians in Illinois & Wisconsin to turn over their land to the United States government, relocating them west of the Mississippi as part of a greater removal effort. American and immigrant settlers then move into the region in greater numbers.
1900. George Sayer decides to build a dairy barn on a hill overlooking the bog, utilizing tamarack logs in the construction process.
1921. Volo Bog is described by W. G. Waterman of Illinois's Northwestern University. This is the first full study of the site.
1958. To protect it from residential development, Volo Bog is purchased by the Illinois chapter of the Nature Conservancy; this is the chapter's first land purchase, supported by local citizen fundraising. They then donate the bog into the care of the University of Illinois, though it's eventually transferred to the Illinois Department of Conservation (now the Illinois Department of Natural Resources).
1970. Volo Bog is dedicated as the 25th Illinois Nature Preserve.
1973. Volo Bog is designated a National Natural Landmark with the U.S. Department of the Interior.
1977. The first Site Superintendant is assigned to Volo Bog and the first interpretive boardwalk trail is constructed.
1980. The Volo Bog visitor center, converted from the structure of George Sayer's old dairy barn, opens to the public.
1983. The Friends of Volo Bog organization forms to protect the site and promote educational activities.
1999-2002. Additional land purchases bring the site to 1,200 acres.