The Herron Rookery is detached from the main body of the Indiana Dunes National Park. It is so named because the portion north of the Little Calumet river used to be home to about 100 great blue heron nests. Although most of the herons have found other homes, the area is still a bird sanctuary. The trail runs along the south bank of the river, with trail heads at both ends. It is about 1.5 miles long, so ~3 miles out and back. It is said to be one of the best trails in the area for spring wild flowers.