Museum of European and Mediterranean Civilisations

Stand still for a moment and listen. Somewhere close, halyards tap against masts in the Old Port. Gulls call over the water. And in front of you, a dark square building seems to dissolve into shadow and light, as if someone had thrown a fishing net over a block of glass. The sun passes through that net and scatters across the ground in small, shifting shapes. This is the Museum of European and Mediterranean Civilisations, which most people in Marseille simply call the MuCEM.

The museum opened in 2013, the year Marseille held the title of European Capital of Culture. That title brought new money and new ambition to a port city that had long carried a rough reputation inside France. The museum was one of the clearest signs of that change. It took a working piece of the harbour, a former port pier known as the J4, and turned it into a place where people come to look at the sea, and at the cultures that surround it.

The architect of the main building is Rudy Ricciotti, who grew up in this region and works close to here. He designed the cube you are looking at, with the architect Roland Carta as a partner on the project. Ricciotti wanted a building that would not compete with the old fortress next door. So instead of stone or bright metal, he chose a dark, matte concrete. From a distance it looks almost soft. Up close, it feels like something grown rather than built.

That lace-like outer skin is the first surprise. It is not decoration hung on a frame. It is made of a special high-performance concrete, reinforced with fibres, and strong enough to be cast in thin, curving branches. The pattern is often compared to coral, to seaweed, or to the shade of a tree. Walk close and run your eyes along it. You will see that the openings are not regular. Some are wide, some narrow, so the light inside changes constantly through the day.

Between that concrete veil and the glass walls of the galleries, a set of ramps winds slowly upward around the building. You do not need to visit the exhibitions to walk them. Many locals come only for this. As you climb, the view keeps changing: the cathedral, the harbour entrance, the open sea beyond. The wind comes through the lattice, and on a hot afternoon this shaded passage is one of the coolest places on the waterfront.

At the top is a roof terrace, and from there comes the second surprise. A long, slim footbridge leaves the roof and crosses open air above the water to the old stone fortress on the other side. It feels almost impossibly thin. Walking it, you move in a few dozen steps from a twenty-first century building into walls that are several hundred years old. The museum treats both sides as one site, and the bridge is the thread that joins them.

That fortress is Fort Saint-Jean. Its main form dates to the seventeenth century, under King Louis the Fourteenth. But it was built around much older structures. The square tower you can see rising from it is linked to King René, a medieval ruler of Provence, and the site also held a house of the Knights Hospitaller, a religious order of soldier-monks from the age of the Crusades. Layers of different centuries sit inside these walls, one on top of another.

Historians often point out an uncomfortable detail about this fort and its twin across the harbour, Fort Saint-Nicolas. They were not only built to guard Marseille from the sea. They were also built to watch over the city itself, which had resisted royal authority. In other words, some of these defences faced inward, toward the people of Marseille. Today the fort is open to everyone, and that history gives a quiet irony to its new role as a public meeting place.

Inside the fort, the paths lead you through terraces, stairways, and gardens. Much of the planting uses Mediterranean species: aromatic herbs, fig trees, olive trees, plants that can survive dry summers and salt wind. On a warm day you may smell rosemary or thyme as you pass. The garden is built around the idea of movement and exchange, because plants, like people, have travelled across this sea for thousands of years.

The collections themselves carry that same idea. Part of the museum's holdings came from an older national museum of French popular arts and traditions in Paris, which closed before this museum opened. Here, those objects found a wider frame. The focus is not one country but a whole sea and the lands around it: daily life, food, belief, festivals, trade, and migration. Exhibitions change, so the galleries you find today may be very different from those a friend saw last year.

The museum also keeps a third site, away from the waterfront, in the Belle de Mai district of Marseille. That building is a conservation and research centre. It stores a large part of the collection and allows researchers to study it. Most visitors never see it, but it is a reminder that what you see in the galleries is only a small selection. Behind each exhibition sits a much larger archive of ordinary objects that people once used and valued.

From almost anywhere on this site, look up and to the south. On the hill above the city stands the basilica of Notre-Dame de la Garde, with its golden statue catching the light. Then look north along the shore. You will see the striped stone of the Cathedral of La Major, and next to the museum the bold overhanging shape of the Villa Méditerranée. Together they show how this short stretch of coast has been rebuilt again and again.

Now come back to where you are standing. Notice the light passing through the concrete lace, the sound of water against the stone below, and the people around you, some here for art, others just here for the shade and the view. As you walk away, look back once more. The cube grows darker as you leave, and the old fort stays pale in the sun. Two different centuries stand side by side here, joined by one narrow bridge.