Marazion and St Michael's Mount Tides

How tides affect the people of Marazion and St Michael's Mount

For approximately half of each day the causeway from Marazion to St Michael's Mount is covered by the tide; St Michael's Mount becomes an island, cut off from Marazion and mainland Cornwall.

Tides are, therefore, very important to the people of St Michael's Mount and, to a lesser extent, the people of Marazion. Life on St Michael's Mount revolves around when the causeway to Marazion is open and when it is not.

From mid-March until early November there is a regular "duty boat" service from Marazion to St Michael's Mount even when the castle is closed. At other times, anyone wishing to travel between Marazion and St Michael's Mount may need to wait for the tide to drop and for the causeway to open.

The Marazion to St Michael's Mount duty boat service is, however, dependent on the weather; if the weather is bad the boats cannot run.

St Michael's Mount also has an "amphi-craft", the 'St Michael'. The St Michael is used for the duty boat service during the winter months and during bad weather in the summer. Although the St Michael can operate in quite rough conditions, it is not an all weather craft so tides are still important.

Tides vary from day to day both in their timing and in height. They are also affected by atmospheric pressure, wind and other weather.

The tide pages on this Marazion Guide website explain briefly Marazion's and St Michael's Mount's tides and the tide predictions used on the website.