The Açudes route, in Ponte de Lima, provides a link between this town on the border of the Ponte de Lima municipality with Ponte da Barca. Unlike the routes downstream from Ponte de Lima, here there is a narrowing of the margins, which reduces the space available for farming. The water, which flows more swiftly here, tumbles into granite blocks, which increase in number as we travel upstream. Man-made fishing structures are commonly found, as are the dams that heighten the sound of the water. The fishing structures restrict the swimming routes of the lamprey on their migration run to spawn, making them easier to catch. The dams divert the water to mills. Arriving at Santa Cruz do Lima, it isn’t long before the ecotrail passes into Ponte da Barca country.