The Tianguá Waterfall is one of the most dramatic natural features around Brotas. The river drops through a basalt canyon in a sequence of falls, ending in a wide swimming hole at the base that is refreshingly cold even in summer. You can visit purely to swim, but most people come as part of a guided canyoning trip, which involves rappelling alongside the falls and scrambling through the canyon on foot.
The surrounding area is cerrado vegetation — the scrubby, biodiverse savanna of interior Brazil — which makes the sudden presence of a river canyon and waterfall feel unexpectedly wild. The hike in is not long but the terrain is uneven, so closed-toe shoes are essential. Tour operators in Brotas include Tianguá in most full-day adventure packages, often combined with a morning on the river or an afternoon zip line.