Concept
Boulogne-sur-Mer (bulɔɲ syʁ mɛʁ; Boulonne-su-Mér; Bonen; Gesoriacum or Bononia), often called just Boulogne (UKbʊˈlɔɪn, USbuːˈloʊn,_buːˈlɔɪn), is a coastal city in Northern France. It is a sub-prefecture of the department of Pas-de-Calais. Boulogne lies on the Côte d'Opale, a touristic stretch of French coast on the English Channel between Calais and Normandy, and the most visited location in the region after the Lille conurbation. Boulogne is its department's second-largest city after Calais, and the 183rd-largest in France. It is also the country's largest fishing port, specialising in herring. Boulogne is an ancient town and was the main Roman port for trade and communication with its Province of Britain. After a period of Germanic presence following the collapse of the Empire, Boulogne was integrated into the County of Boulogne of the Kingdom of France during the Middle Ages. It was occupied by the Kingdom of England numerous times due to conflict between the two nations. In 1805 it was a staging area for Napoleon's troops for several months during his planned invasion of the United Kingdom. The city's 12th-century belfry is recognised by UNESCO as a World Heritage Site (along with other belfries of Belgium and France), while another popular attraction is the marine conservation centre Nausicaa. The French name Boulogne derives from the Latin Bononia, which was also the Roman name for Bologna in Italy. Both places – and Vindobona (Vienna) – are thought to have derived from native Celtic placenames, with bona possibly meaning "foundation", "citadel", or "granary". The French epithet -Mer ("on-the-sea") distinguishes the city from Boulogne-Billancourt on the edge of Paris. In turn, the Boulogne in Boulogne-Billancourt originates from a church there dedicated to Notre-Dame de Boulogne, "Our Lady of Boulogne[-sur-Mer]". The foundation of the city known to the Romans as Gesoriacum is credited to the Celtic Boii. In the past, it was sometimes conflated with Caesar's Portus Itius, but that is now thought to have been a site near Calais which has since silted up.