Why Abu Ayyub al-Ansari anchors the whole site
The emotional center here is the tomb of Abu Ayyub al-Ansari, remembered as a companion of the Prophet Muhammad who died during the siege tradition linked to Constantinople in 671 AD. That is why visitors do not move through this complex like a normal monument crowd: many come to pray, reflect, or pay respects first, and sightseeing happens around that devotional rhythm.
1458 made Eyüp a post-conquest landmark
After the Ottoman conquest of 1453, the site gained new ceremonial weight, and the first mosque was built here in 1458. That early foundation matters because it made Eyüp one of the places where the new Ottoman Istanbul expressed religious legitimacy most visibly. You still feel that gravity when you enter the precinct from the square.
Earthquakes reshaped the mosque you see
The first mosque did not survive unchanged. Minarets were rebuilt in 1733, the earlier structure was badly damaged in the 1766 earthquake, rebuilding started on July 9, 1798, and the current mosque opened in 1800, with more repair work following in 1823. What you see now therefore carries both the memory of the early Ottoman foundation and the form of a later rebuilding.
What to notice in the precinct
Do not rush straight to a single photo angle. Notice how the courtyard, ablution fountain, tomb queue, old shade trees, and cemetery slope all work together as one devotional setting on the Golden Horn. This layered atmosphere is exactly what makes Eyüp Sultan Mosque feel more intimate than Istanbul's grander skyline mosques.