The section along the sand line that separates the Ria de Aveiro from the Atlantic Ocean is one of the most spectacular and scenic stages of the GR57, especially suitable for cyclotourism, given the characteristics of the ground in which it is developed. From Carregal to São Jacinto, always heading south on the EN327, the blue tones that appear to blend the sky into the Ria and vice-versa are breathtaking. The Atlantic, although not visible, hidden behind the dunes that guard and form this peninsula, has a presence that can be enjoyed, either at the Torreira Beach or at São Jacinto. Although we know that geological time is often invisible to the short human life, if we went back to a period before the 10th century, we would have no ground to walk on. This peninsula, one of the most impressive and recent phenomena of the Portuguese northern coastal strip, was formed about a thousand years ago, and the Atlantic bathed towns like Ovar, Estarreja, Aveiro, Ílhavo or Mira. The Ria de Aveiro was born from all this process and this singular sandspit, protected in the area of São Jacinto by a Natural Reserve.