The area, in square metres, of Samba City, which houses the top samba schools throughout the year as they prepare for the annual carnival. Visit the on-site museum which charts the festival's history, see floats being made, try on costumes and practise samba with a live band. Admission 20 reals (£7). sambacity.info
The number of lifeguard posts along the three main beaches (Copacabana, Ipanema, Leblon). Each post's number is associated with a different crowd, from gay, to posers, to families. As well as scanty beachwear and beach volleyball, the shores are also known for surfing.
The best breaks are found on the outskirts of the city. Surf n Stay, on Macumba Beach, is minutes away from seven major surfing spots and offers accommodation in dorms or en suite doubles, plus board hire and a surf school. Doubles from 40 reals (£15). riosurfnstay.com
The percentage of Rio's population living in favelas. These shanty towns have housed the city's poor since the 18th century and were originally settlements of African slaves; it was the resultant cultural jumble that produced samba – the rhythm and dance from which the carnival stems. To learn more about their history, Favela Tours offers itineraries from 65 reals (£24). favelatour.org
The height, in metres, of Pedra Bonita. While Sugarloaf is Rio's most iconic mountain, Pedra Bonita is the ultimate peak for hang gliders and paragliders. Take off from a ramp in Tijuca National Park, drift over the city and land on the beach below. Rio Adventures can organise tandem flights with qualified instructors from 295 reals (£109). rioadventures.com
The length in kilometres of the Presidente Costa e Silva Bridge, linking Rio de Janeiro with the municipality of Niteroi, across Guanabara Bay. It's worth making the trip for the Museum of Contemporary Art, a salute to modernism both inside and out. Renowned Brazilian architect Oscar Niemeyer designed the fruit bowl-shaped building, which is perched on a cliff and houses a dazzling collection of art. Admission is 5 reals (£2). macniteroi.com.br
The number of samba schools that compete at the Sambadrome in the annual carnival. Last year, Unidos da Tijuca won the Best Parade title, for the first time in 74 years. It swept to victory with a performance that included a Michael Jackson impersonator, a pregnant drummer and a float with a dry ski slope and skiing Batmans. The victors are announced on Ash Wednesday. rio-carnival. net