The Southern Hills are the Black Hills' greatest hits, packed into one unforgettable day. Where the Northern Hills offer drama and history, and the Badlands deliver wide-open spaces, the Southern Hills give you everything at once: engineering marvels, wildlife, granite spires, and a lake that looks like it was placed there on purpose.

This is the most dramatic of the three circuits and the most technically rewarding. Iron Mountain Road alone is worth the rental: 17 miles of spectacular scenery that loops back over itself, three tunnels that each perfectly frame Mount Rushmore in the distance, and switchbacks through ponderosa pine that no road planner today would ever consider building. Then Custer State Park opens up with the Wildlife Loop, where herds of bison graze along the roadside, pronghorn antelope roam the grasslands, and friendly burros wander up expecting a pat... and sometimes a snack! The Wildlife Loop offers 18 miles of some of the best wildlife viewing in the American West.

Needles Highway is the grand finale: 14 miles of towering granite spires, single-lane tunnels carved through solid rock, and Sylvan Lake at the northern end is the icing on the cake. Leave Custer by mid-afternoon to experience the Needles in the best light. Plan for a full day, and don't rush it.

Easy additions to this tour include Mount Rushmore, the Shrine of Democracy; the Crazy Horse Memorial, an enormous mountain carving in progress honoring the great Lakota leader; the Indian Museum of North America; and the classic Black Hills towns of Hill City and Keystone.