The largest aquarium in South America is Rio's newest major downtown attraction. You can get an up-close look at some 350 different species (there are more than 8000 animals in all), spread among two dozen different tanks. The highlight is a 3.5-million-liter aquarium with a tunnel through the middle that gives fine views of sharks, rays and shimmering schools of fish gliding past.
To get here, you can take the VLT (which has stops at the metro stations of Cinelândia and Carioca) to the Utopia Aquario stop. There's also a Bike Rio stand out front.