The Port of Boulogne-sur-Mer is a seaport located on the western coast of the Hauts-de-France region, on the edge of the Pas de Calais, the world's busiest strait for international shipping.

[1] Due to the configuration of the Strait, the tidal range (difference in height between high and low tide) in this port is the highest in the region: 8 meters on average at Boulogne-sur-Mer (compared with 5.2 at Dunkirk).

[5][6][7] Legend has it that in the year 633 or 636, during the reign of King Dagobert, a ship without oars or sailors entered the port of Boulogne in unusually calm weather.

According to legend, it was illuminated and contained a wooden relief Virgin Mary “of excellent carving, about three and a half feet high, holding the infant Jesus on her left arm, at the origin of a pilgrimage still alive in the 19th century”, according to Abbé Daniel Haigneré [fr].

Local tradition also has it that this vessel contained a relic of Christ and another of the Virgin Mary, along with a handwritten Bible, said to have been enshrined by Saint Éloy, Bishop of Noyon.

[8][9] In the 18th century, the port of Boulogne was a major center for maritime smuggling with England, known as smogglage or smoglage, particularly for tea, wine and brandy exports.

The port specializes in forestry/paper products, but has a storage area of almost 500,000 m3, and can also handle cement, aggregates and riprap produced in the Boulonnais region.

The second part, covering some 20 hectares, saw the inauguration on September 19, 2009, of a new freight-passenger terminal featuring a double-deck, double-lane gangway capable of adapting to the width of all types of ship.

[22] Conversely, it also helps to conserve water in the Liane during low-water periods, perhaps by reducing the risk of nocturnal asphyxia of fish in a context of eutrophication and anoxia.

[27] It is considered a major obstacle to the upstream migration of migratory fish, yet the Liane is home to a very large eel population.

[34][notes 2][35] Today, optimizing the value of catches, diversifying the use of wild resources and developing aquaculture are among the themes addressed by the Aquimer national competitiveness cluster.

The drop in catches of certain species such as sole, mackerel and whiting has been offset by ever greater volumes of cephalopods (squid and cuttlefish), red mullet and scallops, whose stocks are in excellent condition.

In November, this vessel was replaced by the “Norman Spirit”, a slower conventional ferry offering higher freight capacity.

In March 2010, following a commercial agreement with Transeuropa Ferries, LD Lines made another change of vessel, with the “Norman Bridge” operating a mixed freight-passenger service.

In May 2010, this service was reinforced by a second identical vessel, the “Norman Trader”, for a few months, until early September 2010, when LD Lines finally ceased its cross-Channel activities at Boulogne.

At the end of 2017, the Bassin Napoléon underwent major renovation work, financed by the Communauté d'Agglomération du Boulonnais, with new pontoons and berths available since May 2018.

Fuel (diesel-gasoil) is available on the port itself, quai Chanzy (diesel pump open 3 h before and 3 h after high tide during office hours), as well as fresh water and electricity (220 V/16 A).

A multilingual (French-English-Dutch) website boulogne-marina.fr has also been created, as well as a facebook page 'Marina Boulogne sur Mer' where all the latest marina news can be found.

In 2017, the port welcomed 2,740 visitors for 7,377 overnight stays, with the majority of customers being Dutch, Belgian, English, German and French.

[59] It also has direct and indirect or delayed environmental effects (for example, for currentological and hydrosedimentary reasons, the discharge of sediments into the sea,[60] and the extension of the harbour jetty in the early 1970s may also have played a role in accelerating shoreline erosion at Wissant (Clabaut, 1988, cited by Aernouts (2006)[61]), was once home to a polluting industry (the Comilog plant), and like all ports, it contributes to greenhouse gas emissions and the spread of invasive species worldwide (for example, the first appearance of the crepidula in the northern Seine estuary was reported here[62]).

[64] Its beach has long been considered the most polluted in France (and high levels of metals, including mercury, have been recorded in the port in the past).

Significant efforts have enabled us to achieve 100% compliance in 10 years, with a few black spots still remaining after rainfall (overflow from wastewater treatment plants), which explains why the beach near the port of Boulogne-sur-Mer is closed to bathing.

Having depended in particular on passenger transport (currently at a standstill since September 2010), tourism in the Port of Boulogne remains linked to the success of Nausicaá, the region's leading tourist site, and to the tourist appeal of the town and its surrounding area (the beaches of the Côte d'Opale, the Haute Ville, the château-museum, the Napoleonic Column of the Grande Armée, the regional nature park) and the Fête de la mer de Boulogne-sur-Mer.

[68] In 2007, the CCI would like to create[69] In a global context of climate change, managers will have to deal with a probable rise in sea levels, and an increased risk of high tides and storms.

The Marel Carno Station (automatic[70]) monitors a number of parameters of the marine environment, including; It is to be integrated into the Mersea project (Marine Environment and Security for the European Area), which is a global ocean observation, modeling and forecasting system set up for 4 years (2004-2008) by federating the efforts of 40 European institutes and agencies.

Some are talking about a return to sailing, but in a modernized version, or new engines (using hydrogen or solar energy), or even various fishing adaptations to be developed around a more sustainable management of fishery resources, which we are seeking to better understand with organizations such as Ifremer, universities...).