Where do the characters in "The Lorax" live?

The characters in “The Lorax” live in Thneedville, the artificial, walled town at the center of the 2012 animated film.

Thneedville is a bright, manufactured world with plastic trees, synthetic grass, and no living plants. Its name comes from the Thneed, the versatile garment invented by the Once-ler from Truffula-tree tufts. The town’s artificial environment reflects how completely the natural world has been replaced by consumer products.

The main characters, including Ted Wiggins, Audrey, and the townspeople, live inside Thneedville. Ted leaves the town to find the Once-ler and discover what happened to the trees. The barren landscape outside Thneedville reveals the environmental damage caused by the Once-ler’s expanding business.

A small clarification: the Lorax and the Once-ler are exceptions to the broad description that the characters live in Thneedville. The Lorax belongs to the former Truffula forest, while the Once-ler lives in isolation outside the town. The original 1971 Dr. Seuss book also does not name the town Thneedville; that setting is especially associated with the 2012 movie.