Hagia SophiaConsistently the top recommendation for visitors, and worth allowing a half day rather than squeezing it between other stops.
Local culture beyond the checklistthe Grand Bazaar and the Bosphorus are where Istanbul feels least like a tourist itinerary and most like the actual city.
A well-known second stop: Topkapi PalaceRounds out a first visit nicely alongside the bigger-name sights.
Easy onward travelIstanbul's transport connections make it simple to extend the trip into the rest of Türkiye if you have the time.
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