The historic heart of Petrópolis can easily be explored on foot: The city is fairly flat and extremely safe; even traffic is less hectic than in Rio. Following the directions below will take you to most points of interest.
Starting on the corners of Avenida Ipiranga and Tiradentes, the first thing you see is the Cathedral São Pedro de Alcantara (daily 8am-6pm), a neo-Gothic church named for both the patron saint of the Empire and -- not coincidentally -- the Emperor Dom Pedro II himself. Construction began in 1876, but the celebratory first Mass wasn't held until 1925. Just inside the main doors to the right is the Imperial Chapel containing the remains of the Emperor Dom Pedro II, the Empress Dona Teresa, their daughter Princess Isabel, and her husband (whose name no one remembers). The princess, who often ruled during her father's many trips abroad, lived in the beautiful mansion immediately across the street, now known as the Casa da Princesa Isabel (closed except for special exhibitions). Continuing along the Avenida Koeler as it follows the tree-lined canal, it's a 5-minute walk to the beautiful Praça da Liberdade. The bridge in front of this square offers the best view of the cathedral and the canal. Just behind the Praça da Liberdade is the Museu Casa de Santos Dumont . From here follow Avenida Roberto Silveira, then turn right on Rua Alfredo Pachá to the Palácio de Cristal, Rua Alfredo Pachá s/n (tel. 024/2247-3721; admission R$5; Tues-Sun 9am-6:30pm). Commissioned by Princesa Isabel and built in France, the structure was inaugurated in 1894 as an agricultural exhibition hall. Nowadays, the palace is used for cultural events and exhibits. The tourist information center inside the Palace has a great brochure in English featuring a map plus a listing of all the attractions with their opening hours.
Crossing the bridge to Avenida Piabanha, you come to the Casa Barão de Mauá, Praça da Confluencia s/n (tel. 024/2246-9215). Built in 1854 in neoclassical style by the industrial baron who constructed Brazil's first railway, the grounds of the house are open daily, from 9am to 6pm. The columns surrounding the winter garden are solid iron, made by the baron himself. Admission is free.
Continue by taking Rua 13 de Maio -- right across the street from the Casa Barão de Mauá -- toward the cathedral and then turning left on Avenida Ipiranga at the intersection just before the cathedral. Along this street are a number of interesting buildings as well as some gorgeous mansions and villas. Standing on the right side of the street at no. 346 is the 1816 Igreja Luterana, the oldest church in Petrópolis (open for visitation only during Sun morning service at 9am). On the left side of the street at no. 405 is the Casa Rui Barbosa, the summer residence of the liberal journalist, politician, and positivist who helped found the First Republic. A bit farther along the Avenida Ipiranga at no. 716 is the lovely Casa de Ipiranga, a museum, cultural center, restaurant, and garden . From here it's a simple matter to retrace your steps to the cathedral.
Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.