Seven days in Türkiye does not support a convincing national circuit. It does support one intense world city and one landscape unlike anywhere else, provided the transfer is treated as a visible travel chapter instead of hidden in an overnight bus. Istanbul supplies imperial architecture, neighbourhood life and the Bosphorus. Cappadocia changes the scale completely: walking paths run through eroded valleys, churches occupy carved rock, and underground settlements turn geology into human history. The contrast is the reason this pairing dominates first-trip planning, not a licence to add Ephesus or Antalya between them.
Three Istanbul nights create an arrival evening and two complete days. The first full day belongs to the Historic Peninsula, where major interiors, security lines and prayer times can reshape a schedule. The second crosses water: use a public ferry as transport, then let Kadıköy or Üsküdar reveal a working Asian-side district before returning through Beyoğlu. That division prevents the familiar mistake of treating the city as a row of monuments around Sultanahmet. It also gives bad weather somewhere useful to go without inventing another paid attraction.
Cappadocia receives the same number of nights for a different reason. A Göreme base places several trailheads and the open-air museum close together, but the underground cities and Ihlara corridor require arranged road transport. Make one day local and one day regional. A balloon reservation may determine the wake-up time, yet it must never determine whether the trip succeeds: operators cancel when conditions are unsafe. If the first launch fails, the second morning is a possible retry; if both fail, sunrise from the ground still leaves two strong days of walking and cultural sites.
Fly into Istanbul and home from Kayseri or Nevşehir when the fare and onward network allow an open-jaw ticket. Otherwise return to Istanbul on the final evening only when the international flight leaves the next day; a self-connection across separate tickets needs a larger margin than an airline-protected itinerary. Compare Istanbul Airport with Sabiha Gökçen and compare both Cappadocia airports by the full hotel-to-gate journey. The shortest airtime can create the longest city crossing. This route therefore fixes nights first, checks the fragile onward connection second, and leaves individual museum hours until the official pages are consulted for the actual date.