Brazil covers four time zones. Most of the country—including Rio, São Paulo, Porto Alegre, Salvador, Brasília, and Belo Horizonte—is three hours behind GMT (Greenwich mean time). Manaus and Pantanal are an hour behind those cities, and the far western Amazon is an hour behind Manaus. Fernando de Noronha, an archipelago off Brazil's northeast coast, is two hours behind GMT. From October to March (exact days vary), Brazil observes daylight saving time in most of the country, so in many areas it stays light until 8:30 pm.