About 90 minutes' walk west of Abraão, on the trail to Dois Rios, lie the ruins of one of Brazil's most notorious maximum-security prisons. The Instituto Penal Cândido Mendes was demolished by the federal government in 1994 to ensure it could never be used again; what remains is broken concrete, the foundations of cell blocks, and the rusted iron of cell doors poking through the regrowing forest.
A small museum (Museu do Cárcere) on the same site, housed in a restored prison building, tells the history through photographs, documents, and a few preserved cells. It is sobering, but worth the walk for context — and the trail itself is one of the loveliest on the island, climbing through dense forest and emerging at the small village of Dois Rios on the wild southern coast.