The Süleymaniye Mosque is Istanbul's largest mosque and, many would argue, its finest — superior to the Blue Mosque in every architectural respect except the number of minarets. Sinan built it in seven years for Suleiman the Magnificent, and the interior achieves what the Blue Mosque attempts: a vast, luminous space made coherent by a single great dome. The calligraphy and stained glass are exceptional; the air inside has a quality of stillness that the tourist-heavy Sultanahmet mosques have lost.
The mosque is far fewer visited than its quality merits, because it sits slightly off the main tourist circuit on Istanbul's third hill. The surrounding complex (külliye) includes Sinan's tomb in the garden and the graves of Suleiman and his wife Hürrem Sultan behind the prayer hall. The mosque is still in active use; dress accordingly and avoid prayer times.