The dome of the Notre-Dame basilica towering above the ramparts of the upper town.
The basilica, built on the site of a former cathedral (destroyed after the Revolution) and designed by Monsignor Haffreingue, an amateur architect of genius, was completed in 1866.
It stands as a landmark for the whole city.
Every year a procession is held in honour of Our Lady.
According to legend, an unmanned ship with a statue of the Virgin had sailed into the harbour in 633 or 636.
That was the beginnig of a pilgrimage famous throughout the Middle Ages and even mentioned in Chaucer's Prologue to the Canterbury Tales (line 465).
The present basilica still contains a Romanesque crypt with painted pillars,where Edward II of England married Isabelle of France in 1303.