Go for the culinary, architecture, historic importance, sightseeing.
Perhaps, it is a good thing that Ouro Preto does not have the same international fame of places like Cusco, in Peru; the result of that is the preservation of the city's identity and unique vibe. Once you visit Ouro Preto, it is hard to imagine that during the Brazilian Gold Rush Era, Vila Rica (name formerly given to Ouro Preto, when it was founded and later turned into the Capital of the Minas Gerais State) was the largest city in Brazil. Nowadays, Ouro Preto is a small and vibrant college town that receives a generous number of tourists, mostly domestic, attracted by the city's well preserved colonial architecture, its historical relevance, relaxed atmosphere and the great cuisine.
Ouro Preto is located in the State of Minas Gerais, and it is nested in a beautiful section of the Espinhaço Mountain Ridge, from where you can see the Itacolomy peak, a natural landmark that was a reference point for travelers during the gold rush. Ouro Preto was accidentally discovered by a frontiersman called Antônio Dias in 1698; and founded as a municipality in 1711, under the name of Vila Rica. The name Ouro Preto (Black Gold) was later given to the city due to the dark color of the gold that was found there, which was heavily covered with Iron oxide. The history of Ouro Preto goes on and on, and most of the events are somehow connected with its gold. For instance, Ouro Preto received over 2 million slaves from Africa to work on the prospection and mining of gold (and several local plantations). Several of these gold mines can still be visited today, as well as, some of the slaves quarters, called "Senzalas", in Portuguese. Gold was also one of the triggers for a popular sentiment of Independence from Portugal, due to the heavy taxation imposed on miners. An early independence attempt ended with its lead, Joaquim José da Silva Xavier (aka "Tiradentes"), being hanged on the central square of the city, in 1789. This square is named "Tiradentes" and one of the main places to hang out today.
Ouro Preto is a designated World Heritage Site by Unesco. This hilly old city, with narrow (and often steep) cobblestone streets and dark alleys, where going around the block never takes you back to your starting point; boasts its past wealthy day with well-preserved colonial mansions and houses, over 18 churches in the Baroque and Rococo style, filled with gold; and its several museums.
As you walk around the old town, you need to take a break to taste the typical Minas Cuisine (Cozinha Mineira) which is sort of a Brazilian "Soul Food", often prepared on a firewood stove, served with pork, rice, black beans, collard greens, and a great number of amazing desserts. Also, stop at one of those small bars/pubs that we call "Butecos", to have a sip of the best cachaça in Brazil and grab a "small bite"; perhaps, a "Coxinha de Frango" (a fried dough stuffed with shredded chicken), or a "Pão de Queijo" (a sort of roll made with tapioca flour and cheese) or anything you see on the counter's display window that may look good to you. Food in Minas Gerais is one of the best in Brazil, and Ouro Preto will give you a great opportunity to try them out. Shopping is also unique; you will be amazed with the local handicrafts made out of refurbished wood and semi-precious stones.
If you are young, full of energy and like to party, you may want to consider spending Carnaval (or Carnival) there, but make your booking well in advance. Carnaval in Ouro Preto is old-style street Carnival, with street parades mainly organized by the local fraternities and sororities; which many times also host visitors during that period. In my humble opinion, Carnaval in Ouro Preto is the most original and the best in Brazil.
The best way to get to Ouro Preto is by road; it's only about 62 miles from its capital city, Belo Horizonte; or about 250 miles from Rio de Janeiro. Once you are there, take the opportunity to visit some of the attractions on its outskirts: the historic town of Mariana, the shops of Itabirito and the many waterfalls.
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