O.21 (Turkey)

Otoyol 21
Otoyol 21
Ankara-Tarsus Motorway; Ankara-Tarsus Otoyolu
Route information
	Part of E 90
Length	432 km (268 mi)
Major junctions
From	Gölbaşı, Ankara Province
To	Tarsus, Mersin Province
Location
Country	Turkey
Regions	Central Anatolia, Mediterranean
Provinces	Ankara, Konya, Aksaray, Nevşehir, Niğde, Adana, Mersin
Major cities	Niğde, Tarsus
Highway system
	Highways in Turkey; Motorways List; ; State Highways List; ;

Kırkgeçit Tunnels

Otoyol 21 (English: Motorway 21), abbreviated as O-21, a.k.a. Ankara-Tarsus Otoyolu (English: Ankara-Tarsus Motorway), is a completed toll motorway in the Central Anatolia and Mediterranean regions in Turkey. Currently, it connects Otoyol 20 from Gölbaşı, Ankara with the Adana-Mersin Motorway O-51 at Tarsus in Mersin Province. On its full length, it is part of the European E90. The last part of the highway opened on 16 December 2020.^[1] With a length of 432 kilometres, the O-21 is the longest motorway in Turkey.

Exit list

Province	District	km	mi	Exit	Destinations	Notes
Ankara	Gölbaşı\|Gölbaşı, Ankara\|Gölbaşı	0.0	0.0	K8	O.20 (Ankara beltway) — Ankara
		14.4	8.9	K1	D.260 — Haymana, Ankara
		16.9	10.5	Gölbaşı Toll Plaza
		29.5	18.3	K2	D.750 — Ahıboz
		76.1	47.3	K3	D.753 — Kulu
	Şereflikoçhisar	101.5	63.1	K4	D.757 — Acıkuyu
Aksaray	Sarıyahşi	139.5	86.7	K5	P.68-83 — Sarıyahşi
	Ağaçören	157.5	97.9	K6	Kırşehir connector — Kırşehir
	Ortaköy	178.3	110.8	K7	D.757 — Kırşehir, Ortaköy
	Aksaray	213.6	132.7	K8	D.300 — Aksaray, Nevşehir
Nevşehir	Derinkuyu	241.6	150.1	K9	P.68-83 — Sarıyahşi
Niğde	Niğde	275	171	K10	P.51-78 — Gölcük
				K11	D.765 — Nevşehir
				K11	D.805 — Kayseri
				K12	D.805 — Niğde / Aydın Ave.
	Bor\|Bor, Niğde\|Bor			K13	P.51-51 — Kemerhisar
	Ulukışla			K14	O.21A — Konya
				Kırkgeçit Tunnels
				Çakıt Tunnel
Adana	Pozantı			K15	D.750 — Pozantı	Pozantı north
				K16	D.750 — Pozantı	Northbound exit, southbound entrance only.
				K17	D.750 — Akçatekir
Mersin	Tarsus\|Tarsus, Mersin\|Tarsus			K18	D.750 — Çamalan
				K19	O.51 — Mersin, Adana
				Tarsus Toll Plaza
				K20	D.400 — Mersin, Adana
1.000 mi = 1.609 km; 1.000 km = 0.621 mi Incomplete access Tolled Unopened