The Gaucho coastal strip stretches from Torres to Chui in the south of the state, where Brazil ends - or begins. Its beaches are almost bare, without any vegetation and with sand dunes and lakes separating the mountain ridge from the sea. Rio Grande, the first Gaucho city founded by the Portuguese, has a deserted, white sandy beach known as Cassino stretching for two hundred and forty five kilometres and completely open to the sea, a haven for wintering seals and sea-lions. Rio Grande is the home of one of the most comprehensive oceanographic museums in Latin America. Lagoa dos Patos (Lagoon of Ducks), the largest in Brazil, covers an area of 10 thousand km2, 55 kilometres away from the city of Porto Alegre. The lagoon occupies a wide strip of territory, reaching Pelotas, the state's second city. With its beaches, used for fishing and water-sports, Patos Lagoon is one of the main tourist attractions in Rio Grande do Sul.