The Kâmil Koç bus companyoperating from Offices 144, 145 and 146 at Istanbul‘s Büyük Otogar (main bus terminal) is one of Turkey’s oldest and largest, running buses from Istanbul to these destinations.
Telephone (212) 444 0562; or (212) 658 2000 at Istanbul‘s Büyük Otogar.
Here’s more information on Kâmil Koç buses.
Alphabetical List of Destinations from Istanbul