<Tr> <Td> </Td> <Td> This article includes a list of references, but its sources remain unclear because it has insufficient inline citations . Please help to improve this article by introducing more precise citations . (May 2017) (Learn how and when to remove this template message) </Td> </Tr> <Table> <Tr> <Td_colspan="2"> Sandhills </Td> </Tr> <Tr> <Td_colspan="2"> Region </Td> </Tr> <Tr> <Td_colspan="2"> Sandhills in Hooker County, near sunset in October </Td> </Tr> <Tr> <Th> Country </Th> <Td> United States </Td> </Tr> <Tr> <Th> State </Th> <Td> Nebraska </Td> </Tr> <Tr> <Td_colspan="2"> </Td> </Tr> <Tr> <Th> Part of </Th> <Td> Great Plains, High Plains </Td> </Tr> <Tr> <Th> Rivers </Th> <Td> Niobrara River, Snake River, North Loup River, Middle Loup River, Dismal River </Td> </Tr> <Tr> <Td_colspan="2"> </Td> </Tr> <Tr> <Th> Area </Th> <Td> 19,600 sq mi (50,764 km) </Td> </Tr> <Tr> <Td_colspan="2"> </Td> </Tr> <Tr> <Td_colspan="2"> The Sandhills covers portions of northern and western Nebraska . </Td> </Tr> <Tr> <Td_colspan="2"> </Td> </Tr> <Tr> <Th_colspan="2"> U.S. National Natural Landmark </Th> </Tr> <Tr> <Th> Designated </Th> <Td> 1984 </Td> </Tr> <Tr> <Th_colspan="2"> </Th> </Tr> </Table> <Tr> <Td_colspan="2"> Sandhills </Td> </Tr> <Tr> <Td_colspan="2"> Region </Td> </Tr>

Why is there so much sand in nebraska