Lake Cornelia, a 244 acre glacial lake located six miles northeast of Clarion, was until the early 20th century known as Little Wall Lake. It is the second of the four lakes in Wright County lying in a north to south direction (Morse Lake, Elm Lake, and Wall Lake being the others) that were created some 12,000 years ago by the Des Moines Lobe of the Wisconsin Glacier. It has a mean depth of 9.4 feet and a maximum depth of 20.6 feet.
Early in the 20th century, the town of Cornelia, located on the east shore of the lake was a bustling community. In addition to the post office which had been established in 1893, other businesses included a railroad depot with two northbound and two southbound passenger trains each day, a general store, cafe, blacksmith, grain elevator, lumberyard, a commercial ice operation, a stockyard, and a roller-skating rink which also served as a dance hall at which the Lawrence Welk orchestra played in its early days. Businesses on the west side of the lake included another roller-skating rink with a concession stand, an ice house, a barber shop, a boat livery, a cafe and a bath house. Nothing remains of those businesses today, except for several of the buildings which have been remodeled into residences.
On the north side of the lake today are several playgrounds, an enclosed shelter-house and several open shelters, lake-side camping spots as well as a large campground off the lake, a jetty, two boat launch ramps, a marina/quiet water area with docks, and the Wright County Conservation Board headquarters. On the east, west and south sides of the lake are some 190 homes, with about 75 of them being year-round residences.