MTB route n°16 - Saint-Renan / Ploudalmézeau / Lanildut / Portsall

Milizac-Guipronvel Milizac-Guipronvel
  • Distance 124 Km
  • Difficulty Difficult
  • Loop
Lake Ty Colo
Port of Lanildut
Chapelle St-Samson
Kersaint chapel

About us

124 km to discover the Iroise seaside and countryside.

Through Milizac-Guipronvel, Saint-Renan, Lanildut and Portsall, you can explore part of the Pays d'Iroise Nord.

Mountain biking is a great way to discover sites that mark the history of our Pays d'Iroise! Set off on an adventure on our signposted circuits, which will take you through many of our region's communes.
18 mountain bike circuits guide you through the Pays d'Iroise countryside or along the coast.

Along the way, take the time to put your foot down and read the heritage interpretation panels.

A few rules of safety and good behavior:
- The coastal path is forbidden to ATVs,
- Before setting off, check the condition of your ATV and bring a repair kit,
- Respect the highway code: ride in single file, helmets are strongly recommended: it is compulsory for children under 12 (CSIR of 02/10/15),
- Always take a snack and a drink,
- Respect private property,
- Don't litter, respect nature by using the garbage cans.

The mountain bike topoguide is available from the Iroise Bretagne Tourist Office for €5.

See the bottom of the page for all the activities and restaurants in the area.

Documents to download
Step 1/13:

START: Church parking lot.

This 17th-century building has been altered at various times. The door to the enclosure features 2 kersantite statues from a calvary. The stained-glass windows in the apse, which once depicted Saint Pol Aurélien and Saint Corentin, patrons of the estate, now illustrate the Wedding at Cana and the resurrection of Jairus' daughter by Jesus.

Saint-Pierre and Saint-Paul church and parish enclosure in Milizac

13 enamelled lava panels punctuate the discovery of the town of Saint Renan, bringing to life the highlights of its history, from the legend of Saint Ronan to the memory of the seneschalsea. Approx. 45-minute tour (2 km). Follow the signs on the ground.

You can find the explanatory brochure in one of the Iroise Bretagne tourist offices.

Saint-Renan city tour

In 1957, the Saint Renan marshes revealed a large deposit of tin ore, mined by the Compagnie minière de Saint Renan.

After fifteen years of operation, the deposit was exhausted. Today, seven lakes remain. In the heart of the town, the shores of the "Ty Colo" and "La Comiren" lakes have been landscaped for the enjoyment of walkers.

The smooth waters of the Ty Colo lake were the first in Brittany to host an astonishing board sport: wakeboarding on a cable.

The lakes of Saint-Renan

This street is lined with the houses of the barge masters, all hidden behind their high walls. Most of these beautiful 17th and 18th century homes are topped by half-moon-shaped chimneys known as "English chimneys".


Situated in the northern part of the Chenal du Four, this small Aber is an excellent stopover for yachtsmen on their way to southern Brittany or England. It's also a great base for day trips to Ouessant or the Molène archipelago on a semi-rigid
The port of Aber Ildut is very lively, with seaweed harvesters arriving to drop off seaweed harvested in the Iroise Sea, pleasure boats mooring, and fishing trips by kayak or stand-up paddle... Kayaks and bicycles for hire from the port store.

The port of Lanildut has long since become the biggest seaweed unloading port on the mainland, with 40,000 to 45,000 tonnes of seaweed passing through every year, keeping the famous seaweed harvesters in business. To find out more, visit the Maison de l'Algue, where you can learn all about the history and development of this typical coastal activity.

Port of Lanildut

The little chapel of Saint-Samson, dating from the second half of the 18th century, offers a marvellous panorama facing the ocean. Below the chapel flows a fountain whose miraculous virtue was used not so long ago. Children were immersed in the fountain to give them strength. The presence of a Gallic stele near the fountain attests to the ancient sacralization of the site. Behind the hamlet, a menhir set into an embankment, against which people used to rub to relieve their rheumatism, takes us even further back in time and reinforces Saint-Samson's healing function.

Saint-Samson chapel

Kersaint, "village of saints", owes its name to the story of Saint Tanguy and Sainte Haude, in the 6th century. They were the children of Galon du Chastel, Lord of Trémazan, whose majestic castle ruins can still be seen at Kersaint, near the shore.

A modest religious edifice dedicated to the two saints was erected very early on, on the spot where Haude was beheaded by her brother as the victim of a deception. The du Chastel family replaced it in the 15th century with the present chapel, most of which dates from the 16th century. In 1518, the chapel, dedicated to Notre Dame du Vrai Secours, was elevated by the du Chastels to the rank of collegiate church.

The Kersaint chapel

See you at Pointe du Guilliguy! Up there, a slender cross on a base of rough rock stands near the Guilliguy dolmen. You won't be disappointed: the view over the charming little port of Portsall is simply marvellous. At high tide, the turquoise water comes alive. Despite the many visible rocks and the beacons securing the harbor exit, fishing boats, small sailboats, kayaks and paddles proudly move about.

Le Guilliguy

On the quay, one of the monstrous anchors of the Amoco Cadiz recalls the ecological tragedy of 1978. The sinking of the supertanker caused one of the worst oil spills in history. Take the time to visit the L'Ancre An Eor museum, if it's open, which recounts the event that turned the lives of the entire community upside down.

Port de Portsall

The commune's name is a reminder that it was originally a simple trève of the parish of Ploudalmézeau.
According to tradition, in the 6th century, after landing on Ouessant, Saint Pol Aurélien, future bishop of Léon, set up an oratory and temporary camp near the fountain. The present church, built on the same site 1100 years later, was dedicated to him.

Eglise Saint-Pol Aurélien

Built by the Marquis François III de Kergroadez near Brest, this early 17th-century château is a classic example of Breton Renaissance and defensive architecture. This vast Leonardo residence is built entirely of Lanildut granite, around a square courtyard enclosed by a defensive wall.

Take advantage of the guided tour (in season) to immerse yourself in another era, discovering, room by room, the way of life in the 17th century through the furniture and accessories on display.

Château de Kergroadez

Classified as a historic monument on July 1, 1975, the hermitage of Saint-Hervé houses the ruins of a chapel, a miraculous fountain and a stone cell that is said to have housed the saint.

Hermitage Saint-Hervé

Located at the bottom of the Traon Bouzar, the Vallon Sourd, the Saint-Ergat fountain is a natural spring that has always been frequented by hundreds of pilgrims suffering from rheumatism. The three columns, reused Gallic stelae, bear witness to an ancient cult at this site, later linked to Sant Ergad when he became the patron saint of the Tréouergat parish.

Saint-Ergat fountain
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