The National Audubon Society operates this 2,400-acre wildlife sanctuary along the Platte River. In early spring, more than half million sandhill cranes pass through the area on their northward migration. Trips to crane-viewing blinds are available every morning and evening during March and early April (see website for exact dates). Overnight photography blinds also are available. The Iain Nicolson Audubon Center offers stunning views of the Platte River, interpretive displays, gift shop and trails. Open year-round, Mon-Fri, 9am-5pm; Sun, 1-4pm. Open daily during crane season with extended hours, mid-Feb through mid-Apr. No admission to Audubon Center, donations accepted. $25 per person fee for trips to crane viewing blinds.