Rüstem Pasha Mosque is a small prayer hall lined wall to wall with İznik tile, hidden on a terrace above a crowded market street. Step inside and the walls dissolve into gardens of tulips, carnations and hyacinths, worked in the tomato red that İznik potters mastered for a few decades and then lost. The colour sits slightly raised off the surface and catches the light from the high windows. Tiles climb the piers, frame the mihrab and spill onto the porch outside, thousands of them in all.
Most people walk straight past it. Sinan set the prayer hall on a high terrace over a maze of vaulted shops in the early 1560s, and plain stairways climb from the mat-sellers' bazaar to a courtyard the shoppers below rarely find. It was built for Rüstem Pasha, grand vizier and son-in-law to Suleiman the Magnificent. Restoration has lifted centuries of grime, so the blues and reds read as sharply now as when they were fired. It stays a working neighbourhood mosque, quieter than the great imperial complexes.