Badlands National Park

Where it sits. Badlands National Park covers about 982 square kilometres of south-western South Dakota, an hour east of Rapid City and immediately south of Interstate 90 at the town of Wall. The park's shape follows a geological accident: the Cheyenne and White river systems have cut a ragged escarpment, the Badlands Wall, through a high prairie, dropping several hundred metres in a chaos of striped spires, knife ridges and gullies. Above the Wall the grass is unbroken to the horizon; below it the ground is bare rock. The North Unit holds the loop road and the visitor centre; the South Unit, the Stronghold District, lies within the Pine Ridge Indian Reservation and is co-managed with the Oglala Sioux Tribe.

What built it. The stripes are a stack of sediments laid down between roughly 75 and 28 million years ago: a black marine shale at the bottom from a sea that covered the continent, then yellow mounds of an ancient floodplain, then the pale grey and buff layers of the White River Group, and finally pink and orange volcanic ash blown in from eruptions far to the west. Erosion here is exceptionally fast - about 2.5 cm a year, which means the formations visible today will be gone in perhaps half a million years. That same rapid stripping makes this one of the richest late Eocene and Oligocene fossil beds on earth: three-toed horses, sabre-toothed nimravids, rhinoceros-like titanotheres and ancient camels come out of these slopes routinely, and the Fossil Preparation Lab at the Ben Reifel Visitor Centre lets visitors watch the work in progress.

Lakota ground and hard history. This is Oglala Lakota country, and the Stronghold Unit holds one of the sites where Ghost Dances were held in 1890, in the weeks before the massacre at Wounded Knee 80 km to the south. During the Second World War the United States Army Air Forces seized 1,200 square kilometres of reservation land here for a gunnery range, displacing families with almost no notice; unexploded ordnance is still being cleared, and much of the South Unit is accessible only with tribal guidance. The White River Visitor Centre, operated seasonally by the tribe, is the place to start for that side of the park.

On screen. Kevin Costner filmed substantial parts of Dances with Wolves here between July and November 1989. The Sage Creek Wilderness Area in the park's north-west, reached by the unpaved Sage Creek Rim Road, provides the country crossed by Lieutenant Dunbar and Timmons on the wagon journey to Fort Sedgewick; the enormous buffalo hunt was shot 200 km north-east on the Triple U Ranch near Fort Pierre, then home to one of the largest private bison herds in the world, and the winter camp in Spearfish Canyon. Thirty years later Chloe Zhao returned to the same landscape for Nomadland (2020): Frances McDormand's Fern works as a camp host at Cedar Pass Campground inside the park and takes shifts at Wall Drug up on the interstate, and the walk she takes through the formations was filmed on the park's own trails.

What you actually see today. The Badlands Loop Road, SD 240, runs 50 km from the Northeast Entrance to Wall with more than a dozen overlooks; Pinnacles, Yellow Mounds and Big Badlands are the ones worth stopping at. Short trails cluster near Cedar Pass: the Door Trail crosses a break in the Wall onto raw badlands floor, the Notch Trail climbs a log ladder to a canyon rim view, and the Fossil Exhibit Trail is boardwalked and fully accessible. The Castle Trail runs 8 km one way for those wanting distance. Sage Creek Rim Road is the wildlife route - bison, pronghorn, bighorn sheep and the reintroduced black-footed ferret, one of the rarest mammals in North America, live along it, and the primitive Sage Creek Campground is free.

Getting there and timing. Rapid City Regional Airport is 80 km west; the park is a straightforward detour off I-90 between Rapid City and Sioux Falls. May and June bring wildflowers and thunderstorms, September and October give clear air and cold nights. July highs pass 35C with no shade at all. Winter is severe, with wind chill well below -25C, though the loop road usually stays open. Sunrise and sunset are dramatically better than midday here: low sun picks out the horizontal banding that flat light erases entirely. Two campgrounds serve the park - Cedar Pass with reservable sites and showers nearby, and Sage Creek with none - and the town of Wall, 13 km north, supplies everything else.