Otoyol 7

The motorway is 243 km in length between the Kınalı junction and the Akyazı junction, and is 8 lanes wide (4+4 lanes).

O-7
Northern Marmara Motorway Kuzey Marmara Otoyolu
open   tendered
Route information
Length	462.7 km (287.5 mi) 95 km (59.03 mi) open 336 km (208.78 mi) newly tendered (including connecting roads)
Existed	As Connector 1987-2016, 2016–present
Major junctions
From	O-3 in Kınalı, Silivri
Major intersections	O-2 in Çekmeköy O-4 in Sultanbeyli O-5 in Gebze
To	O-4 in Akyazı
Location
Country	Turkey
Regions	Marmara
Provinces	Istanbul Province, Kocaeli Province, Sakarya Province
Major cities	Kınalı, Istanbul, Gebze, İzmit, Adapazarı, Akyazı
Highway system
Highways in Turkey Motorways List State Highways List
← O-6 → O-20

The completed section of highway crosses the Bosphorus Strait via the Yavuz Sultan Selim Bridge, which was opened in August 2016. The route is intended to serve as the outermost beltway of Istanbul as well as being the third road crossing of the Bosphorus. The route stretches 431 km (268 mi) from Silivri, on the European side, to Akyazı on the Asian side. Connections to the O-4 as well as both the Bosphorus and Fatih Sultan Mehmet bridges will be built as the Northern Marmara Motorway and will bypass Istanbul to the north.

Up to 2016, the only section under construction was the 90 km (56 mi) section from Odayeri to Paşaköy. In this section, 14 tunnels, 61 viaducts, 45 underpasses, and 63 overpasses will be constructed.

The western (Silivri-Odayeri) and eastern (Kurtköy-Akyazı) sections were tendered in early May 2016. Construction was then estimated to take three years and to start in 2016. The section of motorway south of O-3 was constructed in 1987 and was listed as a connector of the O-3 until 2016. The T1 and T2 tunnels on this highway were the location for the world's longest flight through a tunnel.

Main route

Province	District	km	mi	Exit	Destination	Notes
Istanbul	Silivri (Kınalı)	0.00	0.00	K1	-Istanbul/Edirne (Kınalı junction)
	Silivri	12.15	7.55	K2	Silivri junction
	Çatalca	19.00	11.81		Çatalca Service Area
		20.37	12.66		Çatalca KMO - T1 Tunnel
		22.45	13.95		Çatalca KMO - T2 Tunnel
		27.94	17.36	K3	, Çatalca junction
	Çatalca (Nakkaş)	34.43	21.40	K4	Nakkaş junction
	Arnavutköy	37.50	23.30		Yassıören Service Area
		41.60	25.85	K5	Yassıören junction
		48.28	30	K6	Tayakadın junction
		51.00	31.69		Tayakadın Service Area
		54.13	33.64	K7	Terminal 1-Istanbul Airport
		56.52	35.12	K8	Terminal 2-Istanbul Airport
		58.21	36.17	K9	Cargo Terminal-Istanbul Airport
	Eyüpsultan	61.00	37.90	K10	-Mahmutbey	Connects to  , Atatürk Airport
		64.40	40.02		Odayeri Service Area
	Sarıyer	77.00	47.85	K11	Kilyos Cd.
	Sarıyer–Beykoz	85.00	52.82		Yavuz Sultan Selim Bridge	(Toll $3)
	Beykoz	93.00	57.79	K12	Riva Cd.
		101.00	62.76		Riva Tunnel
	Çekmeköy	105.00	65.25	K13	Şile Yolu Cd.
		107.00	66.49		Reşadiye Service Area
		113.00	70.22	K14	O-2/O-6 Connector-Ümraniye,
	Sancaktepe	115	71	K15	-Sultançiftliği,Şile
		117.00	71.46	K16	Atatürk Cd.
	Pendik	125.00	77.67	K17	O-4/O-6 Connector-Pendik,	Connects to Sabiha Gökçen Airport
	Tuzla, Istanbul	137.26	85.29	K18	Formula (Istanbul Park) junction
		139.17	86.48		Istanbul Park Service Area
Kocaeli	Gebze	142.25	88.40	K19	Balçık junction
		146.70	91.16		Mollafenari Service Area
		150.50	93.52	K20	Liman Connector-Gebze,  ,
	Körfez	163.65	101.69		Sevindikli Service Area
		169.38	105.25	K21	Sevindikli junction
	Derince	175.70	109.18	K22	Toylar junction
		178.15	110.70		Kocaeli KMO - T1 Tunnel
	İzmit	183.20	113.84		Kocaeli KMO - T2 Tunnel
		185.50	115.27		Kocaeli KMO - T3 Tunnel
		185.90	115.52		Kocaeli KMO - T4 Tunnel
		189.06	115.48		Kocaeli KMO - T5 Tunnel
		191.82	119.19	K23	-İzmit, Kandıra junction
		194.80	121.05	K24	İzmit junction/
		198.00	123.03		İzmit Service Area
		212.83	132.25	K25	Akmeşe junction
		218.00	135.46		Akmeşe Service Area
Sakarya	Adapazarı	223.81	139.07	K26	-Adapazarı, Kaynarca junction
		231.84	144.06	K27	Karasu junction
	Akyazı	240.00	149.13		Akyazı Service Area
		243.35	145.62	K28	-Ankara, Istanbul, Akyazı junction

Connecting route

Province	District	km	mi	Exit	Destination	Notes
Istanbul	Eyüpsultan	0.0	0.0	-	Işıklar-Ağaçlı Rd. — Ağaçlı
		1.3	0.8	K1	O-6 — Sancaktepe, Istanbul	via Yavuz Sultan Selim Bridge
		4.6	2.9	K15	D.020
		6.3	3.9	Işıklar Toll Plaza
	Arnavutköy	13.2	8.2	K14	Arnavutköy-Habibler Rd. - Fenertepe
	Başakşehir			K13	Habipler - Hasdal connection
		17.3	10.7	K12	Kanuni Sultan Süleyman Rd.
		19.7	12.2	K11	2720 St.
		20.9	13.0	K10	677/19 St.
		21.5	13.4	K9	Süleyman Demirel Blvd.
		21.7	13.5	K19	O-3 West — Edirne	Toll otoyol
	O-3 East — Fatih				Connection to the   O-1 and   O-2
	Bağcılar	23.5	14.6	K181	Halkalı Ave.
	Bahçelievler	25.5	15.8	K182	Mimar Sinan Ave.
		28.1	17.5	K183	Değirmenbahçe Ave.
		29.4	18.3	K184	Sanayi Ave.	Northbound exit, southbound entrance and exit
	Bakırköy	30.1	18.7	K185	D.100 — Çobançeşme
		31.7	19.7	-	Atatürk Havalimanı Ave. — Atatürk Int. Airport	Transition into Boulevard

• 28 December 2023 — At least 10 people were killed and 57 others injured in a multiple-vehicle collision in Sakarya Province, Turkey.