9 Best Sights in Istanbul, Turkey

Only after you enter the Blue Mosque do you understand its name. The inside is covered with 20,000 shimmering blue-green İznik tiles interspersed with 260 stained-glass windows; calligraphy and intricate floral patterns are painted on the ceiling. After the dark corners and stern faces of the Byzantine mosaics in Aya Sofya, this mosque feels gloriously airy and full of light. Indeed, this favorable comparison was the intention of architect Mehmet Ağa (a former student of the famous Ottoman architect Sinan), whose goal was to surpass Justinian's crowning achievement (Aya Sofya). At the behest of Sultan Ahmet I (ruled 1603–17), he created this masterpiece of Ottoman craftsmanship, starting in 1609 and completing it in just eight years, and many believe he indeed succeeded in outdoing the splendor of Aya Sofya.

Mehmet Ağa actually went a little too far, though, when he surrounded the massive structure with six minarets: this number linked the Blue Mosque with the Masjid al-Haram in Mecca—and this could not be allowed. So Sultan Ahmet I was forced to send Mehmet Ağa down to the Holy City to build a seventh minaret for al-Haram and reestablish the eminence of that mosque. Sultan Ahmet and some of his family are interred in the türbe (mausoleum) at a corner of the complex.

From outside of the Blue Mosque you can see the genius of Mehmet Ağa, who didn't attempt to surpass the massive dome of Aya Sofya across the way, but instead built a secession of domes of varying sizes to cover the huge interior space, creating an effect that is both whimsical and uplifting. Note that, as of this writing, the Blue Mosque is undergoing an extensive restoration. Although it remains open to the public (except during services), some of the interior details might be blocked by scaffolding.

On a hilltop opposite Istanbul University is one of the city's most magnificent mosques, considered one of the architect Sinan's masterpieces. The architectural thrill of the mosque, which was built between 1550 and 1557 and fully restored in 2010, is the enormous dome, the highest of any Ottoman mosque. Supported by four square columns and arches, as well as exterior walls with smaller domes on either side, the soaring space gives the impression that it's held up principally by divine intervention. Except for around the mihrab (prayer niche), there is little in the way of tile work—though the intricate stained-glass windows and baroque decorations painted on the domes more than make up for that. The tomb of Sinan is just outside the walls, on the northern corner, while those of his patron, Süleyman the Magnificent, and the sultan's wife, Roxelana, are in the adjacent cemetery. Stroll around the beautiful grounds, and don't miss the wonderful views of the Golden Horn.

Inspired by Aya Sofya and completed in 1506, this domed mosque holds the distinction of being the oldest of the Ottoman imperial mosques still standing in the city. Though the inside is somewhat dark, it has an impressively carved mihrab and the large courtyard has 20 columns made of verd antique, red granite, and porphyry that were taken from ancient buildings.

Muslim pilgrims from all over the world make their way to the brightly colored, tile-covered tomb of Eyüp Ensari (Ayyub al-Ansari)—a companion of the Prophet Muhammad who served as his standard-bearer—at this mosque complex on the Golden Horn. Ensari was killed during the first Arab siege of Constantinople (AD 674–78), and the eternal presence of a man so close to Muhammad makes this the holiest Islamic shrine in Turkey. His grave site was visited by Muslim pilgrims in Byzantine times and "rediscovered" during Mehmet the Conqueror's siege of Constantinople. After the conquest, Mehmet monumentalized the tomb and built a mosque, where investiture ceremonies were held for successive sultans. The mosque currently on the site was built after the original edifice was ruined in the 1766 earthquake. The plane-tree-shaded courtyards and large numbers of visitors imbue Eyüp Sultan Camii with a sense of peace and religious devotion not found in many other parts of this often frenetic city. A vast cemetery has grown up around the mosque. It's best to avoid visiting at prayer times.

This complex consisting of a mosque, religious schools, and other buildings of a pious nature was the largest in the Ottoman empire, and is still one of the most culturally important mosques in the city. Today it remains the heart of Fatih, one of Istanbul's most religiously conservative neighborhoods. The original mosque, which was destroyed by an earthquake in 1766, was built from 1463 to 1470 by Mehmet the Conqueror on the site of the demolished Church of the Twelve Apostles, the burial church of Byzantine emperors from Constantine on. The 18th-century replacement, which has been completely restored, is quite attractive—particularly the extensive stained-glass windows—though probably very little of what you're seeing is original. Behind the mosque is the reconstructed, baroque-style tomb of the Conqueror himself, along with the far plainer tomb of his wife Gülbahar. It's best to avoid visiting the mosque at prayer times.

Temporarily closed for renovation, the Chora Church, formerly a museum and now a mosque, contains dazzling mosaics and frescoes that are considered to be among the world's finest Byzantine artworks. Most of the mosaics, in 50 panels, depict scenes from the New Testament and date from the 14th century. They are in splendid condition, having been plastered over when the church became a mosque in the 16th century and not uncovered until the 1940s. "Chora" comes from the Greek word for countryside; the original church here was outside the city walls that were built by Constantine the Great, but at the beginning of the 5th century AD, Theodosius built new fortifications to expand the growing city, which brought the church inside the walls. The current edifice is believed to have been built in the 12th century. The easiest way to reach Kariye Camii is by taxi or by Edirnekapı-bound bus from Eminönu or Taksim Square. The tree-shaded café outside the mosque is a pleasant spot for lunch before you trek back into town.

The medium-sized Şehzade Camii was built for Süleyman the Magnificent's eldest son, Prince Mehmet, who died of smallpox in 1543 at age 22. This was the great Ottoman architect Sinan's first imperial mosque, and he called it his "apprentice work." The result is quite attractive, although less spectacular than the nearby Süleymaniye. The tranquil gardens contain several imperial tombs—including that of Prince Mehmet, decorated with some of the best İznik tiles in Istanbul.

Built in 1571 for Sokollu Mehmet Pasha, a grand vizier to three successive sultans, this small mosque is not as grand as the Süleymaniye Camii (in the Bazaar Quarter), but many consider it to be one of the most beautiful of the mosques built by master Ottoman architect Sinan. Here, Sinan chose not to dazzle with size but to create a graceful, harmonious whole—from the courtyard and porticoes outside to the interior, where floral-motif stained-glass windows and gorgeous, well-preserved İznik tiles with both floral patterns and calligraphic inscriptions are set off by white stone walls. Inside, the minbar (pulpit), delicately carved in white marble and crowned with a tiled conical cap, is particularly noteworthy.

A dominant feature of the Istanbul skyline, thanks to its prime spot on the Eminönü waterfront, the "new mosque" is known as much for its history as its architecture. Its location, rising out of the Golden Horn, presented formidable engineering challenges to the former apprentice to Sinan, who laid the waterlogged foundations in 1597. Due to sultans' deaths and complicated harem politics, the project wasn’t completed until 1663 by the queen mother at the time, Turhan Hatice. The entrance to the courtyard from the main square offers a marvelous view of the small domes and semidomes that appear to cascade down around the main dome, flanked by two minarets. Inside, almost every square inch of the interior is decorated—from the elaborate, multicolored İznik tiles to the intricately painted domes and gilded minbar—while numerous windows, including in the wall of the mihrab, fill the mosque with light. Note that during the restoration work that was underway at this writing, the mosque wasn't open to the public.