Ilgaz 15 July Independence Tunnel  Ilgaz 15 July Independence Tunnel, shortly Ilgaz Tunnel, ( or "Ilgaz Tüneli"), is a highway tunnel through the Ilgaz Mountains between Kastamonu Province and Çankırı Province in northern Turkey. The tunnel has twin tubes of   The construction cost of the tunnel was budgeted to 572 million (approx. US$200 million as of March 2016). The foundation stone laying ceremony took place on November 9, 2012. Tunnel boring works were completed on April 3, 2016.