Karasudan Kaynarcaya Tunnel Pass Road: Highways 1. Construction of Karasu-Kaynarca-Adapazarı storey intersection commenced by the Regional Directorate. The contracting partner As İnşaat and Yertaş have undertaken the construction of a new bridge over Sakarya River in the 19 km distance between Dortyol lights and the crossing of the Kaynarca-Karasu divided road. There is also a tunnel passage on the route. The tunnel on one of the strips will be 360 meters and the other will be 470 meters. The total contract value of road, intersection and tunnel constructions 77 million 224 thousand 533 lira. As a part of the construction works, the construction of the İzmir Egekent highway, the Büsan and Cement intersections in Konya, and the construction of many roads and intersections, especially the road to Balıkesir-Bigadiç. Yertaş is known as the company announcing its name with the construction of highway tunnels with HEPP and dam transmission tunnels.