The "Sentier des Douaniers" is a coastal path around Brittany that will take you, if you wish, from Mont St Michel, around the coast to a little way beyond Vannes, over 1700 Km. Our aims were a bit more modest and we took a short section from Perros-Guirec to Saint Guirec, the next village along. And rode the bus back.
An early start saw the sailing schools getting ready for the onslaught, and the broad and well-signposted way filled with runners, joggers and walkers as we progressed. The granite coast is rugged, inset with little tidal pools and bays, with impressive rock formations. The pictures aren't the same as being there, but they will give you an idea of what you might see.