Dinan stands at the head of the tidal Rance. Some thirty kilometres of road separate the corsair city from the medieval town, but the link reads most clearly by water: the same tide that rises against the ramparts of Saint-Malo climbs the estuary, passes the tidal power station’s barrage and dies out at the Châtelier lock, a few kilometres downstream of Dinan’s port. Above it, on its spur, the walled town keeps its ramparts, its timber-framed houses and the rue du Jerzual. It is the last stop in the Rance valley, and the most built-up.
Where the tide ends
For centuries, the port of Dinan was the break point between the tidal Rance and the river Rance, and the old bridge was the only land crossing all the way to the estuary. The Town of Dinan notes that the town first prospered from this position, trading early on with England and Flanders. Today, the boundary lies at the Châtelier lock, by the little port of Lyvet. Downstream, the Rance lives to the rhythm of the tide; upstream, the river is canalised as far as the port of Dinan and beyond.
Between the barrage and the Châtelier, this tide is not quite the sea’s. The tidal power station controls how the basin fills and empties, and EDF publishes its level forecasts for the Saint-Suliac tide gauge. The SHOM tide times for Saint-Malo therefore do not apply as they stand on the Rance: for water heights above the barrage, check the Rance water levels page.
Arriving by boat: a cruise set by the locks
In season, the Compagnie Corsaire runs a commented cruise from Saint-Malo or Dinard to Dinan. The trip takes 2 h 45 each way. The boat first goes through the barrage lock, which operates on the hour provided the sea-side level reaches at least 4 metres above chart datum. It then sails up the estuary, past fishing villages and malouinières, where the river widens like a lake before narrowing between steep banks, and finally through the Châtelier lock, which only opens when the tidal Rance holds enough water.
These two locks set the timetable. The company warns that its departures may change according to the requirements of the barrage and the Châtelier, and the Dinan tourist office states that cruise times depend on the tides. Departure dates only appear when you simulate a booking on the company’s website. For the return, the company chartered a coach this summer between place Duclos in Dinan and the Porte de Dinan in Saint-Malo. Check these arrangements when you book: they change from one season to the next.
Other ways to get there
By coach, line 10 of the regional BreizhGo network links Dinan and Saint-Malo; in Saint-Malo, it serves the “Gares” stop. By train, you change at Dol-de-Bretagne: the Saint-Malo–Dol TER takes about a quarter of an hour, then another line runs on to Dinan. By car, allow some thirty kilometres. By bike, according to the tourist office, the old railway line turned greenway links Dinard to the port of Dinan: an option if you are staying on the left bank. For all of these, check the timetables with the operators on the day.
The port and the rue du Jerzual
The port of Dinan-Lanvallay stretches along both banks, below the viaduct. According to the Town, the opening of this structure in 1852 permanently sidelined the old climb up the Jerzual. The quays are now a stopping point for walkers, cyclists and boaters, with café terraces along the water.
From the port, the rue du Petit-Fort climbs to the Jerzual gate, then becomes the rue du Jerzual up to the historic centre. In the Middle Ages it was the only way to the port. The slope is steep, the cobbles uneven, and the stone and timber-framed houses are now home to artists’ and craftspeople’s workshops. The climb calls for good shoes, and the descent for just as much care.
Ramparts, castle, clock tower and Saint-Sauveur
The ramparts still enclose the historic centre for nearly 2.7 kilometres, with four gates. The Town describes them, in the time of the dukes, as the largest in Brittany after those of Nantes and Rennes. The demolition of the Porte de Brest in 1881 led to their listing as a historic monument in 1886. The tourist office offers a “Tour des Remparts” walk of about 1 h 30, which can be combined with its “Vieux Dinan” (Old Dinan) route.
The castle, at the south end of the old town, is a palace-tower built from 1380 for Duke John IV. The castle’s own website dismisses the name “Duchess Anne keep” as folklore. Long a prison, then a museum, it saw its collections moved into storage between 2014 and 2018; since 2019, the visit focuses on the monument, court life and the art of war in the 14th century. In 2026 it is open from 4 April to 3 January 2027, daily until the end of September, then Tuesday to Sunday from October to December.
The clock tower (Tour de l’Horloge), raised in the 15th century by the town’s merchant class, stands more than 45 metres high; in season you can climb to the top for the view over the rooftops. The Basilica of Saint-Sauveur, first recorded in 1123, blends Romanesque and Gothic and holds the tomb containing the heart of Bertrand Du Guesclin. Right next to it, the Jardin Anglais, the parish’s former cemetery, leads to the Tour Sainte-Catherine and its plunging view over the port.
Along the Rance
The towpath leaves the port in both directions. Upstream, it leads to Léhon, its lock and its abbey of Saint-Magloire, on the canalised Rance. Downstream, it passes the Taden plain and reaches the port of Lyvet and the Châtelier lock: this is where the Rance becomes a tidal estuary again, and where boats wait for the lock to open.
When to go
Dinan is a good outing for a grey day: its streets and monuments can be visited in any weather, and the town is one of the shelters listed on the Saint-Malo in the rain page. Thursday is the big market day, a tradition the Town traces back to the Middle Ages. In 2026, the Fête des Remparts association is holding Arsonora, a medieval music festival, from 16 to 30 October in Dinan and the surrounding area; the Fête des Remparts itself, held every two years, is announced for July 2027.
The simplest combination remains the valley: the barrage, Saint-Suliac and the Mordreuc slipway on the way up, Dinan at the end of the day. The other day trips are on the around Saint-Malo page, and the Rance sites in the list below and on the interactive map.
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