Arribas e Dunas da Concha de São Martinho do Porto

A group of dunes and cliffs that protect the Bay of São Martinho do Porto. It is located at 19 kilometres from Alcobaça and it is a geographical accident that, because of its shape, like a perfect shell, is unique in Portugal and in the rest of Europe. It has a three kilometres long stretch of sand and it is located between the Santana hillock to the south and the Farol hillock to the north.