From Wazeopedia
Turkey road shield Freeway.PNG
  • Freeways are motorways designed for high speed traffic, connected to other roads exclusively by ramps. All freeways in Turkey are toll roads and numbered O-x or O-xx, where x is the road number.
Road shield International E.PNG
If the road connects to the International E-road network in Europe, it is assigned an E-xx number as well.