From 8am to 10am in the morning, 5pm to 8pm in the evening. These are the common and expected rush hours. We also have unexcepted traffic which is possible any time and anywhere in the city. Please don't forget that Istanbul is one of the biggest metropolitans in the world with more than 15 million population. Be prepared and try to use public transportation such as tram, subway, funicular or boats during these rush hours.
