The preserve protects 25 miles ( 40 km ) of the south bank of the Niobrara river and 8.5 miles ( 14 km ) of the north bank .
The Niobrara Valley Preserve is one of the largest areas of land devoted to conservation in the Great Plains .
The preserve protects 25 miles ( 40 km ) of the south bank of the Niobrara Valley Preserve river and 8.5 miles ( 14 km ) of the north bank .
The Niobrara Valley Preserve is one of the largest areas of land devoted to conservation in the Great Plains .