Across the strait at the mouth of Guanabara Bay lies Niterói, founded in 1573 and until 1975 the capital of the old state of Guanabara. Though lacking the splendour of the city of Rio, Niterói, with a population of half a million, has a busy commercial centre, an important museum and lively nightlife - well worth a visit, certainly, as it's also the gateway to the Costa do Sol to the east.
Buses out of Niterói head east along the Costa do Sol, which is dominated by three large lakes - Maricá, Saquerema and Araruama, separated from the ocean by long, narrow stretches of white sandy beach - and flecked with small towns bearing the same names as the lakes. Approximately 10km directly south of Niterói are a number of smaller lakes, too, collectively known as the Lagos Fluminenses, though these aren't really worth the effort to get to as the water is polluted. However, the evil-smelling sludge which surrounds them is purported to have medicinal properties. The main lakes are also muddy, but at least the water here is clean and much used for water sports of all kinds. The brush around the lakes is full of wildlife (none of it particularly ferocious), while the fresh, salty air makes a pleasing change from the city streets.
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