Twice a day, the tide rises and falls on the Arcachon Bay at times and at heights which vary daily.

This natural phenomenon is due to the gravitational pull of the moon and sun on the ocean.

When the sea reaches its highest or lowest level and seems to stop moving, it is slack water. As for the coefficients, they are expressed in hundredths and vary from 20 to 120, to indicate the strength of the tide, and therefore the depth of the water. To find out the time of the next swim or crab fishing, click here !