The Dells of the Wisconsin River, also called the Wisconsin Dells (from Old English �
dæle
��, modern English “dale”), meaning “valley”, is a 5-mile (8-km)

gorge A canyon (from ; archaic British English spelling: ''cañon''), or gorge, is a deep cleft between escarpments or cliffs resulting from weathering and the erosive activity of a river over geologic time scales. Rivers have a natural tendency to cu ...

on the

Wisconsin River The Wisconsin River is a tributary of the Mississippi River in the U.S. state of Wisconsin. At approximately 430 miles (692 km) long, it is the state's longest river. The river's name, first recorded in 1673 by Jacques Marquette as "Meskous ...

in south-central

Wisconsin Wisconsin () is a state in the upper Midwestern United States. Wisconsin is the 25th-largest state by total area and the 20th-most populous. It is bordered by Minnesota to the west, Iowa to the southwest, Illinois to the south, Lake Michi ...

, USA. It is noted for its scenic beauty, in particular for its unique

Cambrian The Cambrian Period ( ; sometimes symbolized Ꞓ) was the first geological period of the Paleozoic Era, and of the Phanerozoic Eon. The Cambrian lasted 53.4 million years from the end of the preceding Ediacaran Period 538.8 million years ago ( ...

sandstone Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicates) ...

rock formations and

tributary A tributary, or affluent, is a stream or river that flows into a larger stream or main stem (or parent) river or a lake. A tributary does not flow directly into a sea or ocean. Tributaries and the main stem river drain the surrounding drainage ...

canyon A canyon (from ; archaic British English spelling: ''cañon''), or gorge, is a deep cleft between escarpments or cliffs resulting from weathering and the erosive activity of a river over geologic time scales. Rivers have a natural tendency to ...

s. The formations are divided into the "Upper Dells" and the "Lower Dells" by the Kilbourn Dam. The cliffs, some over 100 feet (30 m) high, and side canyons are closed to the public to protect sensitive ecological features. The viewing of the rock formations by water is a popular tourist attraction in the area. The nearby city of Wisconsin Dells is the center of summer tourist activity, much of it in the form of the

theme park An amusement park is a park that features various attractions, such as rides and games, as well as other events for entertainment purposes. A theme park is a type of amusement park that bases its structures and attractions around a central ...

s unrelated to the river features. The Dells of the Wisconsin River is owned by the

Wisconsin Department of Natural Resources The Wisconsin Department of Natural Resources (WDNR) is a government agency of the U.S. state of Wisconsin charged with conserving and managing Wisconsin's natural resources. The Wisconsin Natural Resources Board has the authority to set policy ...

. It was established as a State Natural Area in 1994.

Description and formation

The Dells was formed during the Last Glacial Period approximately 15,000 years ago, although the rock itself is much older, dating from the

Cambrian Period The Cambrian Period ( ; sometimes symbolized Ꞓ) was the first geological period of the Paleozoic Era, and of the Phanerozoic Eon. The Cambrian lasted 53.4 million years from the end of the preceding Ediacaran Period 538.8 million years ago ( ...

approximately 510–520 million years ago when the area of Wisconsin was at the bottom of a shallow sea. Approximately 19,000 years ago, the Dells was at the extreme western margin of the continental

glacier A glacier (; ) is a persistent body of dense ice that is constantly moving under its own weight. A glacier forms where the accumulation of snow exceeds its ablation over many years, often centuries. It acquires distinguishing features, such as ...

. However, the Dells itself was never covered by glacial ice sheets – it was part of the large

Driftless Area The Driftless Area, a topographical and cultural region in the American Midwest, comprises southwestern Wisconsin, southeastern Minnesota, northeastern Iowa, and the extreme northwestern corner of Illinois. Never covered by ice during the last ...

that was bypassed by the ice. The melting of the glacier formed

Glacial Lake Wisconsin Glacial Lake Wisconsin was a prehistoric proglacial lake that existed from approximately 18,000 to 14,000 years ago, at the end of the last ice age, in the central part of present-day Wisconsin in the United States. Formation and demise Before t ...

, a lake about the size of

Great Salt Lake The Great Salt Lake is the largest saltwater lake in the Western Hemisphere and the eighth-largest terminal lake in the world. It lies in the northern part of the U.S. state of Utah and has a substantial impact upon the local climate, particul ...

Utah Utah ( , ) is a state in the Mountain West subregion of the Western United States. Utah is a landlocked U.S. state bordered to its east by Colorado, to its northeast by Wyoming, to its north by Idaho, to its south by Arizona, and to it ...

and as deep as 150 feet (45 m). The lake was held back by an ice dam of the remaining glacier. The eventual bursting of the ice dam unleashed a catastrophic flood, dropping the lake's depth to 50 feet (15 m) and cutting deep, narrow gorges and unusual rock formations into the sandstone seen today.

Ecosystem

The area of the Dells provides a mixture of plant communities, including northern and southern

oak An oak is a tree or shrub in the genus ''Quercus'' (; Latin "oak tree") of the beech family, Fagaceae. There are approximately 500 extant species of oaks. The common name "oak" also appears in the names of species in related genera, notably '' ...

pine A pine is any conifer tree or shrub in the genus ''Pinus'' () of the family Pinaceae. ''Pinus'' is the sole genus in the subfamily Pinoideae. The World Flora Online created by the Royal Botanic Gardens, Kew and Missouri Botanical Garden accepts ...

forests, as well as

oak savanna An oak savanna is a type of savanna—or lightly forested grassland—where oaks (''Quercus ''spp.) are the dominant trees. The terms "oakery" or "woodlands" are also used commonly, though the former is more prevalent when referencing the Mediter ...

, moist cliffs, and dry cliffs. The cliffs provide unique niches for plants, some of which are very rare in Wisconsin, including: *Cliff cudweed (''Gnaphalium obtusifolium var saxicola'' ), which is known in only two places on Earth – in the Dells and in the Kickapoo Valley, grows on protected rock ledges. *Lapland azalea (''Rhododendron lapponicum'') *Round-stemmed false foxglove (''

Agalinis gattingeri ''Agalinis gattingeri'', the roundstem false foxglove, is an annual hemiparasitic forb measuring between 10.5 and 60.5 cm in height. Description ''Agalinis gattingeri'' is an annual species with upright, slender, round stems which are hair ...

'') *

Maidenhair spleenwort ''Asplenium trichomanes'', the maidenhair spleenwort, is a small fern in the spleenwort genus ''Asplenium''. It is a widespread and common species, occurring almost worldwide in a variety of rocky habitats. It is a variable fern with several subs ...

(''Asplenium trichomanes'') *Fragrant fern (''Dryopteris fragrans''). Among the rare animals in the dell are six

dragonfly A dragonfly is a flying insect belonging to the infraorder Anisoptera below the order Odonata. About 3,000 extant species of true dragonfly are known. Most are tropical, with fewer species in temperate regions. Loss of wetland habitat threat ...

species, including the Royal river cruiser (''Macromia taeniolata''), six rare

mussel Mussel () is the common name used for members of several families of bivalve molluscs, from saltwater and freshwater habitats. These groups have in common a shell whose outline is elongated and asymmetrical compared with other edible clams, which ...

s and numerous species of birds.

Cultural history

The cultural history of the area stretches back several thousand years, from early Paleo-Indian people to the more recent Native American peoples, such as

Ho-Chunk The Ho-Chunk, also known as Hoocągra or Winnebago (referred to as ''Hotúŋe'' in the neighboring indigenous Iowa-Otoe language), are a Siouan-speaking Native American people whose historic territory includes parts of Wisconsin, Minnesota, Iow ...

, Sac, and

Menominee The Menominee (; mez, omǣqnomenēwak meaning ''"Menominee People"'', also spelled Menomini, derived from the Ojibwe language word for "Wild Rice People"; known as ''Mamaceqtaw'', "the people", in the Menominee language) are a federally recog ...

, who left behind effigy and burial mounds, camps and village sites, garden beds, and rock art. The Dells were made famous in 1886 by the photographer H. H. Bennett, who took the first stop-action photo of his son jumping onto Stand Rock. The Kilbourn Dam, completed in 1909, raised the water level of the Upper Dells by about , flooding some of the caves and rock formations in Bennett's photographs.

Protected status

The area is now owned by the

and was designated a State Natural Area in 1994.

References

External links

Stewards of the Dells of the Wisconsin RiverDown and Out in a Repurposed Troop Carrier
{{DEFAULTSORT:Dells Of The Wisconsin River Driftless Area Protected areas of Adams County, Wisconsin Protected areas of Columbia County, Wisconsin Protected areas of Juneau County, Wisconsin Protected areas of Sauk County, Wisconsin Rock formations of Wisconsin State Natural Areas of Wisconsin Landforms of Adams County, Wisconsin Landforms of Columbia County, Wisconsin Landforms of Juneau County, Wisconsin Landforms of Sauk County, Wisconsin 1994 establishments in Wisconsin Protected areas established in 1994