The Driftless Area or Paleozoic Plateau is a region in the American Midwest noted mainly for its deeply carved river valleys. While primarily in southwestern Wisconsin, it includes areas of southeastern Minnesota, northeastern Iowa and extreme northwestern Illinois (see map at right). This region includes elevations ranging from 603 to 1,719 feet (184 to 524 m) and covers an area of 16,203 square miles (42,000 km²). This region's peculiar terrain is due to its having escaped glaciation in the last glacial period.

The term "driftless" indicates a lack of glacial drift, the material left behind by retreating continental glaciers.

Retreating glaciers leave behind silt, clay, sand, gravel, and boulders — called drift. Glacial drift includes till (unsorted material) and outwash (layers deposited by meltwater streams). While some glacial drift has been discovered, this is said to be of Pre-Illinoian age about 500,000 years old.

What is clear is that the region has been subject to the regular catastrophic effects of glacial lake outburst floods involving the cataclysmic collapse of ice dams holding in such bodies as Glacial Lake Agassiz, Glacial Lake Grantsburg, and Glacial Lake Duluth (see Jökulhlaup).

Alexandra Daddario (born March 16, 1986) is an American actress, known to film audiences as Annabeth Chase in the 2010 film Percy Jackson & the Olympians: The Lightning Thief. Daddario was also in The Squid and the Whale, All My Children, The Babysitters, The Attic, The Hottest State, White Collar, and Bereavement. She will star as the protagonist "Heather Miller" in the 2012 horror film The Texas Chainsaw Massacre 3D.

Daddario was born in New York and was raised in the Upper East Side; her parents are lawyers.

She is of Italian and Czechoslovakian descent.

She wanted to be an actress when she was a child but her first television role did not come about until she was 16 years old, when she booked the role of victimized teen Laurie Lewis on All My Children. At the same time, she was a sophomore attending a traditional girls school in New York. "I was finishing my sophomore year of high school at the Brearley School in New York," Daddario said. "I would not have been able to continue my education there."