Istanbul is a city in Turkey. Famous for kebabs, but there are many vegan alternatives around, from specific restaurants to street food.
çiğ köfte - traditionally made with raw meat, it became illegal to sell that version (although if you are offered homemade çiğ köfte it is likely meat, so ask). luckily they decided to make it vegan-friendly! it contains bulgar, tomato paste, red pepper paste, spices, chopped onions, and green onions, fresh mint and parsley, pomegranate syrup, and lemon are added. it is eaten as a dürüm with bread (3TL), or you can buy a porsyon with just the ingredients for about 6 to 10TL.
Mercemek çorba (lentil soup) - available in lokantas and restaurants everywhere, normally between 1 and 3 lira. occasionally made with fat however, so ask if you can! comes with free bread always.
Fasulyeli Pilav (beans and rice) - occasionally cooked with chicken or beef broth, so ASK! costs around 3TL, very filling. also available in kiosks, restaurants, and lokantas.
http://govindaistanbul.com/ - vegetarian indian restaurant in Beyoglu with plenty of vegan options, mains typically less than 10TL. not bad food, but there are better places that other people can add.
Felafel House - just off taksim square, walk down the street next to simit saray, perpendicular to cumhuriyet cadessi, about 100m down. dürüm for 6TL, highly recommended.
really there are plenty more if you do some research and have some cash to spare.
some good phrases - et siz mi? (without meat?)
substitute et for these other words:
balık - fish
süt - milk
yümürta - egg
tavuk - chicken