Most international and domestic flights arrive at Istanbul's Atatürk Airport, although an increasing number of both domestic and international flights on low-cost carriers fly into the newer Sabiha Gökçen Airport on the Asian side of the city.
There is a slow metro directly from Atatürk Airport to the Aksaray neighborhood, where you can then catch a tram to Sultanahmet, but you’ll have to walk a short way between these two rail lines, as they don’t actually connect. It’s considerably less of a hassle to take one of the regular shuttle buses operated by the Havataş company (10 TL to Taksim) or a taxi. Taxis and shuttle buses can be found at the main exit from the terminal building. There is no rail link to Sabiha Gökçen Airport, so you’ll need to take a Havataş shuttle bus (13 TL to Taksim) or a taxi (www.havatas.com.tr).