From: here

As part of the project, which will begin Sept. 3, certain traffic lanes throughout the city will be closed to all traffic except buses between certain hours.

The Istanbul Metropolitan Municipality is set to launch a new project called “Public Transportation Line” in an effort to relieve the city’s myriad traffic problems.

As part of the project, which will begin Sept. 3, certain traffic lanes throughout the city will be closed to all traffic except buses between the hours of 7 and 10 a.m. and 4 and 8 p.m. on weekdays.
Officials have said they expect the project to persuade 17,000 more people to use public transportation instead of private vehicles daily. 

The project will first be piloted on the Topkapı-Aksaray and Şirinevler-Mahmutbey routes before being extended to include the Topkapı-Aksaray-Taksim, Kızıltoprak-Bostancı-Tuzla, Beşiktaş-Maslak and Yenikapı-Başakşehir routes. 

If the initiative is successful, it will be extended to a larger area, according to officials.