First week of december is the only time I can go. I'm interested in sigtseeing, cruising the Bosphorus, doing tours, going to restaurants, etc. Is there anything I shouldn't do or place I shouldn't go because of the cold weather in december?
It does get cold in Istanbul - it will rain and sometimes snow. Wrap up warm though and head out into the city and you will be fine. If it gets too much, then head to a tea shop and get warm again.
I prefer a city when it is the off season as its often not so crowded and you can move around much more freely. over 6 years ago