Bison Cow and Calf Crossing Wildlife Loop Road, Custer State Park

Custer State Park's Wildlife Loop Road runs 18 miles through the southern Black Hills of South Dakota, cutting straight through open range where the park's bison herd roams freely. That herd numbers around 1,300 animals, one of the largest publicly held bison herds in the world, and sightings along this stretch of pavement are common enough that rangers post warning signs for drivers. Calves are born in the spring, arriving a reddish-brown color that darkens to the adult's blackish-brown coat within a few months. Each fall the park holds its Buffalo Roundup, a decades-old tradition where riders drive the herd together for health checks and population management, drawing thousands of spectators to watch cowboys work cattle that can weigh up to 2,000 pounds.