Nordstern Hotel Galata is only a few steps away from Karaköy Tram Station.
If you are coming from IST Ataturk Airport, take the M1 Havalimani (Airport) – Aksaray line and leave the tram at Zeytinburnu, the 6th stop. You should use another token to enter the tram turnstiles on the same platform in order to take the T1 Zeytinburnu-Kabatas line . Take the trams marked Kabatas and you will reach to Karaköy station. The whole journey will take almost an hour.