High Tides in Saint-Malo: 2026 Dates and Tips

In Saint-Malo, the sea never serves as just a backdrop. It transforms the landscape, reveals beaches and rocks, then returns to surround the forts and strike the foot of the ramparts. During the high tides, this metamorphosis takes on a particularly spectacular dimension.

From the Château du Colombier, a four-star hotel in Saint-Malo, it takes just a few minutes to reach the corsair city and observe one of the most fascinating natural phenomena in Brittany.

What is the high tide phenomenon?

Tides are mainly caused by the gravitational pull exerted by the Moon and the Sun on the oceans. When the Earth, Moon, and Sun are almost aligned, at the time of the full moon or new moon, their forces combine.

The sea then rises higher and falls lower. The difference in level between high tide and low tide, called the tidal range, becomes particularly significant.

In France, the intensity of the tide is expressed by a coefficient between 20 and 120. From a coefficient of 90, one generally speaks of a high tide. When it exceeds 100, the spectacle becomes exceptional.

However, one should not confuse high tide with a storm. A high coefficient primarily indicates a significant difference between high and low tide. The phenomenon becomes even more impressive when it coincides with wind, swell, or an atmospheric depression.

Why are high tides so impressive in Saint-Malo?

The bay of Saint-Malo and that of Mont-Saint-Michel have a particular geographic configuration. The shape of the coastline and the shallow depth of the seabed progressively amplify the movement of the water.

During the highest coefficients, the sea level can vary by more than twelve meters in a few hours. At low tide, a vast intertidal zone is revealed and allows access on foot to Fort National, Grand Bé, or Petit Bé. A few hours later, these islets are once again completely surrounded by the sea.

On Sillon beach, the breakwaters gradually disappear under the waves. Near Bon-Secours beach, the seawater pool and its famous diving board also offer a striking reference point to measure the ocean's rise.

The next high tides in Saint-Malo in 2026

Several high tides can still be observed in Saint-Malo during the fall and winter of 2026:

• September 11, 12, and 13, 2026: announced maximum coefficient of 102;

• September 27, 28, and 29, 2026: coefficient of 99 and equinox tide;

• October 10, 11, and 12, 2026: coefficient of 95;

• October 27, 28, and 29, 2026: coefficient of 100;

The precise times of high tide and low tide vary each day. It is therefore essential to consult the official Saint-Malo high tide calendar before each excursion.

Where to admire the high tides in Saint-Malo?

The Sillon causeway is one of the most famous places to observe the rising tide. From a sheltered spot, one can watch the sea progressively cover the beach and surround the breakwaters.

The ramparts of Saint-Malo Intra-Muros offer a more panoramic view of Fort National, Grand Bé, and the port entrance. The bastion of Holland also allows one to admire the bay and Bon-Secours pool from above.

At low tide, a walk towards Grand Bé offers a remarkable perspective on the ramparts. However, it is important to carefully check the time of the rising waters: the sea returns quickly and can isolate careless walkers.

Some essential precautions

High tides should always be observed with caution. Even in good weather, the sea can rise quickly and encircle an islet or cover a passage in a few minutes.

It is recommended to stay in secured areas, not to approach dikes when waves break over them, and to follow the instructions of local authorities. For a walk on the intertidal zone, wear suitable shoes and begin your return well before the time of the rising tide.

Experience the high tides from the Château du Colombier

Attending the high tides of Saint-Malo is an experience in itself. At dawn, the bay reveals almost endless stretches of sand. A few hours later, the ocean returns to the ramparts and completely redraws the landscape.

After this bracing spectacle, the Château du Colombier offers a particularly pleasant return to calm. This elegant 18th-century malouinière, transformed into a four-star castle hotel, is nestled in the heart of a six-hectare park.

The rooms and suites, historic lounges, and Breton-inspired table compose a refined interlude on the doorstep of Saint-Malo. Whether for a weekend in Brittany or a longer stay, the Château du Colombier is thus a privileged address to discover the high tides, the corsair city's ramparts, and the landscapes of the Emerald Coast.

In Saint-Malo, each tide offers a new face to the sea. But during high coefficients, the spectacle becomes unforgettable: an invitation to contemplate the power of nature, before returning to the serenity and elegance of the Château du Colombier.