Late September in the Black Hills smells like pine and cold creek water, and the aspens are starting to go gold along the high roads. If you have one free day this fall, spend it on the loop that begins at our Keystone front door and ends at our Hill City one.

The timing is good right now. Fall color in the Hills usually peaks from late September into early October, with the higher elevations turning first and the valleys holding their color into mid-October. One guide we like puts the sweet spot at September 25 through October 10. That window is open.

Morning: Iron Mountain Road out of Keystone

Start early. The light is softer, the pullouts are empty, and you will want a jacket until the sun gets over the ridgelines.

Iron Mountain Road (US 16A) leaves Keystone heading south and runs 17 miles of curves toward Custer State Park. It is the road with the pigtail bridges, those wooden corkscrews that let you drop or gain altitude in a hurry, and three rock tunnels. The tunnels are cut so that Mount Rushmore sits framed in the opening, far off in the distance. Heading south, use the pullouts and look back toward the mountain. With yellow leaves in the foreground, it is the picture people take home.

Give it at least an hour. Nobody drives Iron Mountain Road fast, and nobody should.

Midday: the Needles and Sylvan Lake

Iron Mountain Road and the Needles Highway are two pieces of the Peter Norbeck Scenic Byway, named for the South Dakota senator and conservationist who planned and surveyed most of the roads in Custer State Park.

The Needles Highway (SD 87) is 14 miles of granite spires, tight switchbacks and two narrow tunnels. The Needles Eye Tunnel is 8 feet wide and 9 feet 9 inches high, so if you are traveling in a big pickup, a trailer or an RV, measure before you go. Plan on an hour or more here too, longer if you stop for every spire that catches the light, and you will.

A few things worth knowing:

• The loop passes through Custer State Park, which requires a park entrance license. Details are on the South Dakota Game, Fish and Parks website.
• The Needles Highway closes to vehicles with the first snow of the season and does not reopen until April 1 or later. In the Hills, that first snow can come without much notice, so if this drive is on your list, sooner beats later.
• If you are in the area Friday, September 25, the Custer State Park Buffalo Roundup brings about 1,300 bison thundering in off the prairie, with the Arts Festival running September 24 through 26. Expect more traffic in the park that week.

The Needles spill out near Sylvan Lake, which is the right place for a long lunch. The water holds the reflection of the rocks and the turning trees, there is an easy trail around the shore, and if you have the legs, the trail to Black Elk Peak starts here too.

What to pack for the road

The full byway takes three to four hours of driving, and most people turn it into a whole day. That means snacks, and we have opinions about snacks.

We have been making candy in the Hills since 1977, and a good share of what leaves our shops in the fall ends up riding shotgun on these roads. Fudge travels well. So do caramels, toffee and our bear paws: pecans, soft caramel and chocolate, made by hand in small batches the same way they have been for decades. A bear paw eaten at a Needles Highway pullout, with the air cold enough that the chocolate stays firm and snaps a little, tastes about as good as candy gets. If you are traveling with someone watching their sugar, we make sugar-free candy too, and our coffee and tea bar is there for those chilly early starts.

Our advice is simple: stop at the Keystone shop on your way out in the morning, and save room for the Hill City shop on the way home.

Evening: Hill City, and one last look at Rushmore

From Sylvan Lake it is a short drive north to Hill City, where the loop ends on Main Street. It is a good place to walk off a day in the car, and the pace slows down once the summer crowds thin out.

If you still have energy after dinner, Mount Rushmore is lit every night of the year. The ranger-led evening lighting program, though, runs only through the end of September, so this is the last week to catch it before it wraps for the season. After that, the sculpture is still illuminated after dark, just without the program.

Come see us this fall

Our Keystone shop stays open into the fall before closing for the winter, and our Hill City shop is open all year, so whichever end of the loop you start from, the kettles will be going. Stop in, say hello and let us know how the leaves looked up high. We always want to hear.

Turtle Town Keystone, 117 Winter St · Turtle Town Hill City, 205 Main St