Associated Press (AP) — Every day, ferries of all shapes and sizes glide across the waters of Istanbul, their wakes intertwining to form intricate lattices of churning foam. The passenger boats are more than just a means of transportation — they’re entrenched in the historic city’s identity, as memorable as its skyline and as constant as the cries of seagulls.

They carry not just people, but also their stories.

Forty million commuters, tourists, vendors and other travelers ride the Istanbul Metropolitan City Lines every year, according to official figures. Trips can range from as little as 10 minutes to several hours, depending on the destination.

For some passengers, the vessels are a scenic commute to work, at times turning into temporary offices where phones ring, laptops hum and voices compete to be heard over the sound of roaring engines.

For others, the boats provide a floating refuge, a brief escape from the grind of daily life in a swarming city of 16 million people.

“I feel that when you travel by ferry… you replenish energy that has been diminished,” said Ali Akgun, who has lived in Istanbul for nearly 50 years. “I love the sea.”

The ferries travel on dozens of routes across the Sea of Marmara, a wholly Turkish body of water, as well as the Bosporus, the strait that both divides and bridges Europe and Asia.

Visiting Istanbul for the first time, Leila Bihi, from Morocco, experienced her first ferry ride between continents.

“It’s already quite special to go from one bank of the (Bosporus) to the other,” she said. “Looking at monuments that are modern and ancient during the call to prayer. … It’s a bit reminiscent of the whole city, its history, its mystical side.”

For centuries the Ottoman Empire, modern Turkey’s predecessor, used maritime routes for not only travel, but also military expeditions. Its capital, Constantinople, was a major center of trade due to its strategic location flanked by critical waterways.

This enduring bond with the sea continues in Istanbul, where water has always been more than a scenic backdrop — it’s embedded in the fabric of the centuries-old city, shaping its character and the lives of its residents.

“I think it’s the most beautiful stage in the world,” said Ramin Kargozari, a musician who makes a living playing his guitar while riding ferries. “Making music on the water, on a ferry, is great.”