The Sundance Sea was an epeiric sea which existed in North America during the mid to Late Jurassic Period of the Mesozoic Era. It was an arm of what is now the Arctic Ocean, and extended through what is now western Canada into the central western United States. The sea receded when highlands to the west began to rise. Image:Mantell's Iguanodon restoration.jpg This article is a . You can help My English Wiki by expanding it.