The city consists of a number of these partially separated districts - Praia Grande, Sao Domingos, Icarahy, Jurujuba, Santa Rosa, Sao Lourenco, Ponta d'Areia and Barreto - all together covering 8 or 9 m.
An electric street railway connects all the outlying districts with the ferry stations of Praia Grande and Sao Domingos.
Within these bays are beaches of white sand, called praias, such as the Praia da Icarahy, Praia das Flechas and Praia Grande, upon which face low tile-covered residences surrounded with gardens.
Since the beginning of the 20th century large sums have been borrowed and expended on new avenues, the widening and straightening of old streets, and the improvement of the water-front between the Passeio Publico and the southern extremity of the Praia de Botafogo by the construction of a grand boulevard, partly on reclaimed land.
Most prominent among the asylums is the Hospicio Nacional for the insane, on the Praia da Saudade, Botafogo, which was erected 1842-52, and is one of the most completely equipped institutions of its class in the world.
The greatest development has been northward and westward, where are to be found the suburbs of Cidade Nova, Sao Christovao, Engenho Novo, Praia Formoso, Pedregulho, Villa Isabel, Tijuca, and a number of smaller places extending far out on the line of the Central railway.