Approaching Alcântara by boat is an experience in itself as you view its church domes, red tile roofs, and lithe imperial palms slowly emerge from a swathe of emerald jungle. Despite the many ruins, there are over 300 17th- and 18th-century mansions spread around the hilltop in various states of disrepair.

The main square of Praça da Matriz is truly impressive. Lined on three sides by once grand palaces, and with a splendid view overlooking the bay, the heart of the square is dominated by the rust brick ruins of the Igreja Matriz de São Mathias. In the center stands the pelourinho (whipping post used for slaves) tattooed with the Portuguese crown’s coat-of-arms.

On one side of the praça sits the Museu Histórico (9 a.m.–2 p.m. daily, R$1). Occupying an azulejo-covered mansion that belonged to of one of Alcântara’s aristocratic families, the museum displays a small collection of engravings, furnishings, and objects that evoke the city’s days of glory. Included is the iron bed specially made for the visit of Emperor Dom Pedro II.

On Rua da Armagura (Street of Bitterness), you can see the ruins of the Palácio Negro, which served as the slave market, and of the Casa do Imperador. Alcântara’s leading families fought tooth and nail over who would have the privilege of building the house that would lodge Dom Pedro II during an official visit. To the townspeople’s eternal disappointment, despite the lavish welcome they had prepared for him, the emperor never made it to Alcântara (rumor has it he was waylaid by a seductive Indian maiden).

Rua Grande is also full of treasures, including the 17th-century Igreja do Carmo (8 a.m.–1 p.m. and 2–5 p.m. Mon.–Fri., 9 a.m.–2 p.m. Sat.–Sun.), whose original baroque splendor has been restored to its former glory.

A short walk from the town brings you to the fairly primitive Praia da Baronesa. Framed by jungle, the beach is a nice place to sit at a barraca and feast on fresh fish and icy beer while watching for guarás. A diet of pink shrimp explains the lipstick-red plumage of these birds (known in English as scarlet ibises). Their appearance against the canopy of green foliage presents a shocking contrast.

Also in the vicinity of Alcântara is Brazil’s satellite-launching center, home of the Brazilian space program (visitors aren’t allowed).