This excellent map series covers Turkey in 7 sheets. These are the most detailed maps available short of the overpriced Turkish topographic maps. Edirne, Istanbul, Marmara. This is an attractive, albeit expensive, map of Turkey. One side has a shaded relief map of the country and an inset map of Istanbul.
All maps have places of interest marked.
Harita Genel Komutanligi. A good quality street map. Covers the main tourist sections of Istanbul, including both banks of the river. 65-4592IS 1 sheet, folded. Illustrates the geology of this eastern European country.