The Guindy, a tributary of the Jaudy, forms wide meandering wooded banks and is home to a number of remarkable sites and monuments, including the Passerelle Saint François, the aqueduct known as l'Évêque, the picturesque hamlet of Guindy with its old mill, and numerous bird-watching sites.
Departing from Tréguier town hall, you will follow the signposted N°10 trail as it plunges into the valley, first on the left bank before returning via the heights on the right bank to Saint Tugdual Cathedral.