Praia do Cassino is the world's longest sea beach and is located in the southernmost of the Brazilian coast, on the South Atlantic Ocean, in the Rio Grande do Sul state. It is purported to be the longest uninterrupted sandy seashore in the world, with various sources measuring it from 212 kilometres to 254 kilometres, stretching from the Molhes at the entran…Praia do Cassino is the world's longest sea beach and is located in the southernmost of the Brazilian coast, on the South Atlantic Ocean, in the Rio Grande do Sul state. It is purported to be the longest uninterrupted sandy seashore in the world, with various sources measuring it from 212 kilometres to 254 kilometres, stretching from the Molhes at the entrance of the Rio Grande seaport in the north to the mouth of the Chuí Stream, on the border with Uruguay, in the south. Due to the coastline paradox, it is difficult to determine both its length as well as its proclaimed status as the longest beach in the world, as the resulting measurements are highly dependent on the resolution at which a beach is recorded. The more accurately the nooks and crannies of a given beach are measured, the longer the beach will inevitably become. As such, 80-Mile Beach in Western Australia is possibly the longest beach in the world.