You’re looking at Teatro Municipal, one of the most charmingly opulent buildings in all of Brazil. It’s located in the neighborhood called Cinelandia, just off Avenida Rio Branco. Cinelandia was once home to a cluster of grand old movie palaces, with Teatro Municipal as the crown jewel.
This great opera venue was built from 1905 through 1909, and renovated in the 1970s. Its design was inspired by the Paris Opera. Teatro Municipal seats almost 2,400. I didn’t make it inside when I was there, but next time I’m in Rio I’d like to get a ticket.