This is the main attraction around this part of the city. The holiest Islamic shrine in the city, the complex includes, right next to the mosque, the tomb of Abu Ayyub al-Ansari (Eyüp Ensari Türbesi), the standard bearer of Prophet Mohammad, died and buried here during the first Muslim siege of Constantinople (674-678 AD). The neighbourhood was named after him. Muslims flock here (in such huge numbers that sometimes you have to queue for a few minutes before entering the tomb) also to see a rather uninteresting plaque made of plastic, which is purported to be Mohammad's footprint. The interior of the tomb, covered with fine tiles/faience, is nonetheless well worth a look, however. It is also interesting to see the devout Muslims leaving the place by walking backwards through its exit hallway, as not to turn their backs to al-Ansari's catafalque, though obviously no one expects everyone to quit the place in the same manner.