Rocinha is home to some 70, 000 people, according to the last census figures, but is widely thought to have considerably more residents.

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One of the most visited favelas in the city is Rocinha.

FORBES: Favela Tourism Provides Entrepreneurial Opportunities in Rio

When trafficking factions clashed in Rocinha, a Rio favela, earlier this year, the state government sent in 1, 000 police and asked the federal government for army help.

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With a gentle, softly spoken demeanor at odds with his heavily tattooed appearance, he peppers his speech with interesting facts about Rocinha, its history and its eccentric personalities.

FORBES: Favela Tourism Provides Entrepreneurial Opportunities in Rio

Zezinho is deeply passionate about Rocinha and the favela.

FORBES: Favela Tourism Provides Entrepreneurial Opportunities in Rio

His success tour company Favela Adventures and blog Life in Rocinha has seen him called in to consult on tourism projects in other favelas, including the recently police pacified Prazeres.

FORBES: Favela Tourism Provides Entrepreneurial Opportunities in Rio

Born in Rocinha to a father from the northeast of Brazil and American mother, Zezinho grew up in the favela before living in the U.S. on and off until 2008, when he decided to return to Rocinha for good.

FORBES: Favela Tourism Provides Entrepreneurial Opportunities in Rio