Spring Creek Prairie Audubon Center, 11700 SW 100th St. near Denton, protects more than 1,160 acres, mostly native tallgrass prairie, with about 4 miles of trails, more than 235 bird species and wagon ruts of the Nebraska City–Fort Kearny cutoff, listed on the National Register. Trails are open sunrise to sunset daily and admission is free; visitor center hours vary by season. Phone (402) 797-2301.