Bosphorus Bridge

Listen first. Beneath the steady hum of traffic, there is the slap of water against stone, the cry of gulls, and the low horn of a ferry pushing upstream. Above you, a thin steel deck hangs in the air between two continents. On a windy day, you can almost feel the strait moving under it, a current of salt water running between the Black Sea and the Sea of Marmara.

This is the Bosphorus Bridge. Since 2016, its official name has been the 15 July Martyrs Bridge, in memory of the people who died during the failed coup attempt that summer. Many Istanbul residents still call it simply the first bridge. That nickname tells you something important. For most of this city's long history, there was no bridge here at all.

Think about that for a moment. Istanbul has been a great city for well over fifteen centuries. Byzantine emperors and Ottoman sultans ruled from these shores. Yet, until the twentieth century, the only way to cross from Europe to Asia was by boat. Rowing boats, sailing boats, and later steam ferries carried people, animals, and goods back and forth across the current, day after day.

The bridge opened in 1973. The timing was deliberate. That year marked fifty years since the founding of the Turkish Republic, and the bridge was presented as a symbol of the modern nation. It was the first permanent road crossing over the Bosphorus. On the day it opened, Europe and Asia were joined here for the first time by a fixed structure that anyone could drive across.

The design came from the British engineering firm Freeman Fox and Partners, the same firm behind the Severn Bridge in Britain. You can see the family resemblance if you look closely at the cables. The vertical hangers that hold up the deck are not straight. They are angled, forming a long zigzag pattern. This inclined arrangement was intended to help the deck resist movement in the wind.

Here is a detail many visitors miss. The deck itself is shaped a little like an aircraft wing. Its slim, aerodynamic steel box sections let wind slide over and under it, rather than pushing against a flat wall. That is why the roadway looks so thin from the shore. It is not a heavy slab. It is a carefully shaped steel shell, light enough to hang from cables.

The numbers are worth hearing. The main span between the two towers is 1,074 metres. When the bridge opened, it was among the longest suspension spans in the world, and the longest outside the United States. The two towers rise around 165 metres. The deck sits high above the water, so that the largest ships in the strait can pass beneath it without slowing down.

And those ships are part of the scene. The Bosphorus is one of the busiest waterways on Earth. Oil tankers, container ships, and bulk carriers move through it, along with fishing boats and the city's white ferries. Stand on the shore for a few minutes and watch. A huge vessel will slide under the deck, and suddenly the bridge looks even higher, like a line drawn across the sky.

Now look at the two ends of the bridge. On the European side, it lands near Ortaköy, a waterfront neighbourhood of narrow streets and cafés. At the water's edge stands the Ortaköy Mosque, a nineteenth century Ottoman mosque with tall windows and pale stone. Photographers love it because the mosque and the steel towers appear together in one frame, old and new side by side.

On the Asian side, the bridge comes down near Beylerbeyi. There, along the shore, sits Beylerbeyi Palace, built in the nineteenth century as a summer residence for the Ottoman sultans. So this single crossing connects two waterfront districts that already had long histories of their own. The bridge did not create these neighbourhoods. It tied them together.

A second surprise. You probably cannot walk across this bridge. Pedestrian access has been closed for many years, mainly for safety reasons. But once a year, the rule changes. During the Istanbul Marathon, runners cross the deck on foot, from Asia to Europe. It is one of the very few marathons in the world where you begin on one continent and finish on another.

The bridge also changed how the city grew. Once cars could cross easily, new homes, offices, and roads spread along both shores. Traffic grew so quickly that a second bridge, the Fatih Sultan Mehmet Bridge, opened farther north in 1988. A third, the Yavuz Sultan Selim Bridge, followed in 2016 near the Black Sea. Today, rail tunnels under the strait carry even more people between the continents.

When night falls, watch the bridge carefully. Colour-changing lights run along the cables and towers. Sometimes they glow in slow waves of blue and purple. On national days, they often show red. The reflections stretch out across the dark water, broken by the wakes of passing boats. Many people in Istanbul say the city does not really look like itself until those lights come on.

So take one last look before you go. Follow a single cable from the top of a tower down to the deck, and then across to the far shore. On one side is Europe. On the other is Asia. Between them, the water keeps moving, the ferries keep crossing, and the traffic keeps flowing above. As you walk away, listen again for the gulls and the ferry horns. They were here long before the bridge, and they are still part of this crossing today.