Kadıoğlu Tunnel is part of the Samsun-Ordu Highway D.010E70 within the Black Sea Coastal Highway, of which construction was carried out by the Turkish Nurol-Tekfen-Yüksel joint venture.[1] The 116 and 150 m (381 and 492 ft)-long twin-tube tunnel carrying two lanes of traffic in each direction.[2] The Kozbükü Tunnel follows the Kadıoğlu Tunnel in direction Ordu.
The tunnel was opened to traffic on 7 April 2007 by Turkish Prime Minister Recep Tayyip Erdoğan.[2] Dangerous goods carriers are not permitted to use the tunnel.[3]