The Great Tides Show
Contemplate the high tide show is a must-see on the Opal Coast. The coastal horizon widens in a tonic atmosphere. To walk there safely, you need to be well informed, even more so during the equinox tides. It is also an opportunity for an educational approach to this phenomenon known since Antiquity.
Understanding the phenomenon of tides
Tides are a fascinating natural phenomenon for young and old! Seeing the sea retreat sometimes very far away is synonymous with a walk on the coast... where the sea was present shortly before. At Calais XXL, for example, it is the opportunity to walk at the foot of the cliffs of Cap Blanc Nez, between Sangatte and Escalles.
This grandiose natural spectacle has a scientific explanation that is not always easy to explain. Here are some elements to answer children's questions!

The phenomenon of tides has been observed since ancient times. The great breakthrough came in the 17th century thanks to Isaac Newton. This English scientist made discoveries about gravitation and the Earth's attraction. The movement of water is for him linked to the attraction exerted by the Sun and especially the Moon. When the Earth, Moon and Sun are roughly aligned, attractiveness increases and coefficients increase. This is especially the case during the 2 equinoxes, when the Sun is facing the equator and the length of the day equals the length of the night. In the Napoleonic period, the French scientist Pierre-Simon de Laplace established the method of calculating tide times.
Tips for walking safely during high tides
The essential tool: it's the tide table! This booklet is available free of charge at the Calais XXL Tourist Office or online. A tide cycle lasts about 12 hours. There are therefore about 6 hours between a low tide and a high tide: this leaves time to enjoy the immense space that the sea leaves us for walking. The important thing is to check the tide times carefully so as not to get caught out.
Tide Times 2025XXL format tides
The strength of the tides depends on the coefficient. Each tide has its coefficient, indicated on the tide table. When the coefficients reach or exceed 100 for a few days, These are high tides! This phenomenon of high tides is even more spectacular during the equinox tides, in spring and autumn. This is where the vastness is revealed, inviting you to take a walk! But always with the necessary precautions.
The big tides 2025
Friday February 28
Morning 99 – afternoon 104
Saturday March 1
Morning 108 – afternoon 110
Sunday 2 March
Morning 111 – afternoon 109
Monday 3 March
Morning 107 – afternoon 102
Friday 28 March
Morning 97 – afternoon 104
Saturday March, 29
Matin 109
Sunday 30 March
Morning 112 – afternoon 114
Monday April 1
Morning 114 – afternoon 111
Tuesday April 2
Morning 107 – afternoon 102