Formosa is a Goiás city northeast of Brasília, useful not because the centre is charming, but because the surrounding cerrado is unusually rich. Within a day trip are tall waterfalls, clear pools, sinkholes, and prehistoric rock markings that make the plateau feel older and wilder than the highway approach suggests.
The headline sight is Itiquira Falls, a 168-metre drop in a protected municipal park. The Bezerra district adds the Bisnau Archaeological Site and Waterfall, where rock carvings sit close to swimming water, and Buraco das Araras, a huge quartzite sinkhole with forest inside it.
Formosa is not a polished resort town, and you need a car or arranged transport for the best places. But if you are in Brasília and want a day with real landscape rather than another cafe or mall, it earns the trip.