Otoyol 21
Otoyol 21, abbreviated as O-21, a.k.a. Ankara-Tarsus Otoyolu or currently Niğde-Tarsus Otoyolu or, is a partly complete toll motorway in the Central Anatolia and Mediterranean regions in Turkey. Currently, it is connecting Gölcük in Niğde Province with the Adana-Erdemli Motorway O-51 at Tarsus in Mersin Province. On its full length, it is part of the European E90.
