Welcome to South Dakota. Point of interest U.S. Highway #85 at this point is called The South Dakota - Spearfish Canyon Scenic Byway - for information see attached linl for driving directions. The Canam Highway - Wyoming / South Dakota State Line to the North Dakota / South Dakota State Line Black Hills National Forest stretches for 1.2 million acres, offering outdoor adventure like hiking, biking and camping amidst stunning scenery. Find grassy mountain meadows, towering granite peaks, deep canyons, cascading trout streams and clear, clean lakes.