Mihrimah Sultan Mosque, Üsküdar

Listen for a moment. A ferry horn sounds low across the water, and gulls cry above the pier. Feet shuffle off the boats and into the square. The air smells of salt, diesel, and toasted simit, the sesame bread rings sold from red carts. And just above all this movement, raised on its stone terrace, a grey dome sits calm and still. This is the Mihrimah Sultan Mosque, and it has watched travellers step ashore here on the Asian side of Istanbul for almost five centuries.

Many locals simply call it the İskele Camii, which means the Pier Mosque. The name tells you its purpose. Üsküdar was the great gateway between Istanbul and Anatolia. Caravans, pilgrims, soldiers, and merchants all passed through on their way east, or arrived here before crossing to the old city. A mosque at the water's edge was the first thing they saw, and the last thing they left behind. It worked as a welcome and as a farewell at the same time.

The woman behind the name was Mihrimah Sultan. She was the daughter of Suleiman the Magnificent, the most powerful Ottoman sultan of the sixteenth century, and of Hürrem Sultan, his influential wife. Mihrimah was married to Rüstem Pasha, who served as grand vizier, the empire's chief minister. She was one of the wealthiest women of her age. She used that wealth the way Ottoman royal women often did — by funding public buildings that served ordinary people.

To design this complex, she turned to Mimar Sinan, the chief imperial architect. Mimar simply means architect, and Sinan would go on to design many of the mosques that shape Istanbul's skyline today. But this building came early in his career. It was completed in the 1540s, years before his grand Süleymaniye Mosque across the water. So here you are looking at a master who was still testing ideas. Some of the solutions you see here he would refine again and again.

Now look at the front of the building. Here is the first thing many visitors miss. The mosque has a double porch. There is an inner portico with domes, and then a second, outer porch in front of it, covered by a deep, wide roof. This outer porch was a practical gift. Travellers who arrived late for prayer, or who simply needed shelter, could rest here out of the sun and rain. It is a building that thinks about people waiting for a boat.

In front of the porch stands the ablution fountain. Muslims wash their hands, face, and feet before prayer, and this fountain serves that ritual. It sits under a broad canopy. Stand near it and you will hear the soft sound of running water mixed with the noise of the square. On a hot afternoon, people sit here simply because it is cooler. The fountain is part of the daily life of the mosque, not only a decoration.

Step back and look up at the shape of the roof. A central dome rises in the middle. Around it, half-domes push outward on three sides, which makes the interior feel wider and more open. Notice that there is no half-dome on the entrance side. Two slender minarets, the towers used for the call to prayer, frame the building. Their sharp pencil-like tips are typical of Ottoman design. From the water, they help mark the shoreline.

Now think about where the sea used to be. Today the mosque stands back from the water, with a road and a square between them. But over the centuries, the shoreline here was filled in and pushed outward. Once, the waves came much closer to this terrace. That raised platform you climbed is not only for elegance. It lifted the mosque above the busy, often muddy waterfront, and it still gives the building a quiet distance from the traffic below.

The mosque was never meant to stand alone. Ottoman mosques were usually the centre of a larger charitable complex. Here, Mihrimah's foundation included schools for religious study and for young children, and facilities to serve travellers. Some of these buildings survive around the mosque today, in changed forms. As you walk the edges of the courtyard, look for low stone walls, small domes, and windows that seem to belong to older rooms. They are traces of the wider community that once gathered here.

Before you step inside, a note on manners. This is an active mosque. Remove your shoes at the entrance and carry them in your hand or place them on the shelves. Women should cover their hair, and everyone should cover shoulders and knees. Avoid visiting during the five daily prayers, especially the Friday noon prayer, when the space is full. Speak softly and do not walk in front of people who are praying.

Inside, the light is gentle. Windows set at different heights let daylight fall across the carpet in soft bands. Look for the mihrab, the niche that shows the direction of Mecca, and the minbar beside it, the tall stair-like pulpit used for the Friday sermon. Look up and you will see painted decoration across the dome and arches. Much of the paintwork comes from later restorations, so the colours you see are not all from Sinan's time.

There is also a story that people love to tell. Mihrimah has a second mosque in Istanbul, at Edirnekapı, on the European side, also designed by Sinan. Legend has it that Sinan was secretly in love with the princess. According to one popular tale, on a certain spring evening, the sun sets behind one of her mosques as the moon rises over the other. Historians treat this as romance, not record. But it is a sweet idea to carry with you.

When you walk back down the steps, pause in the square. Across from the mosque stands an ornate eighteenth-century fountain built for Sultan Ahmed the Third, with carved panels and a wide, overhanging roof. It belongs to a later and more decorative age. Put the two side by side in your mind. One is calm and solid, the other playful. Between them, you can see how Ottoman taste changed over two hundred years.

Now look around you once more. The ferries still leave every few minutes. People still hurry past the porch to catch a boat, and some still stop to pray before they cross. In that sense, the building is doing exactly what it was built to do. As you walk to the pier, glance back over your shoulder. Watch the two minarets line up against the sky — the same view countless travellers saw as they left Üsküdar behind.