 The largest nature preserve in the area is the Balcones Canyonlands National Wildlife Refuge, a preserve northwest of Austin near Burnet and Marble Falls comprising .Other preserves in the area include the Wild Basin Wilderness Preserve, the Indiangrass Wildlife Sanctuary, and the Onion Creek Wildlife Sanctuary.These preserves are all part of the Heart of Texas Wildlife Trail, a network of trails and sites for viewing wildlife habitats, created by the Texas Parks and Wildlife Department.