According to the U.S. National Park Service, "Great Smoky Mountains National Park is one of the most pristine natural areas in the East." Encompassing over 500,000 acres, it is the largest national park in the Eastern United States, protecting many of the unique ecological communities found in the Southern Appalachian region. Within the park 2,115 miles of streams drain the park, which varies in elevation from about 875' to 6,643'. Diversity of Water Mite genera is high in the national park (Radwell & Smith, 2007). According to the National Park Service, such diversity is prevalent because the park served as a refuge for biota during the last Ice Age:

The Great Smoky Mountains are among the oldest mountains in the world, formed perhaps 200-300 million years ago. They are unique in their northeast to southwest orientation, which allowed species to migrate along their slopes during climatic changes such as the last ice age, 10,000 years ago. In fact, the glaciers of the last ice age affected the Smoky Mountains without invading them. During that time, glaciers scoured much of North America but did not quite reach as far south as the Smokies. Consequently, these mountains became a refuge for many species of plants and animals that were disrupted from their northern homes. The Smokies have been relatively undisturbed by glaciers or ocean inundation for over a million years, allowing species eons to diversify. (U.S. NPS, para. 3)