The Minho river widens into a tidal estuary just below Caminha, sweeping past sandbanks and a long forested island before emptying into the Atlantic. From the riverside promenade you can walk south along the bank for about two kilometres to the mouth, where the river meets the sea between two low headlands.
It is a fine stretch for an early-evening walk — flat, easy, with herons and egrets in the shallows and Galicia rising green on the far side. At low tide the sandbars are exposed and clam-diggers come down with their forks. A small wooden bird hide sits halfway along, and at the end the estuary opens out into the broad horizon of the Atlantic.