O-1
The First Beltway 1. Çevreyolu
Route information
Length	24 km (15 mi)
Existed	1973–present
Major junctions
West end	D.100, O-3 in Eyüp, Istanbul
East end	Bağdat Ave. in Kadıköy, Istanbul
Location
Country	Turkey
Regions	Marmara
Provinces	Istanbul Province
Major cities	Istanbul
Highway system
Highways in Turkey Motorways List State Highways List
→ O-2

Otoyol 1 (English: Motorway 1), abbreviated as O-1 and locally referred to as Freeway 1 (Turkish: 1. Çevreyolu), is a controlled access highway in Istanbul, Turkey. The O-1 serves as the inner freeway and is one of three freeways in the city, the others being the O-2, and O-7, as well as connecting the European and Asian parts of the city via the Bosphorus Bridge.

It starts Osmaniye neighborhood in Bakırköy district on the European part, runs through the city over the Golden Horn and the Bosphorus, and terminates in Söğütlüçeşme neighborhood of Kadıköy district on the Asian part. Otoyol 1 is toll-free, however the Bosporus Bridge is a toll bridge in the eastward direction only, having its toll plaza at the Asian side. The O-1 is connected via three feeder highways to The Second Beltway.

Exit list

Province	District	km	mi	Exit	Destinations	Notes
Istanbul	Eyüpsultan	0.0	0.0	K1	O-3 — Edirne / D.100 — Kapıkule
		1.2	0.75	K2	Rami Kışla Cd.	Eastbound entrance and westbound exit
		1.6	0.99	K3	Yavedut Cd. / Beylerbeyi Cd. / Halıcıoğlu Okmeydani Cd.
	Golden Horn	1.9	1.2	Haliç Bridge
	Beyoğlu	2.8	1.7	K4	Halıcıoğlu Okmeydani Cd.	Westbound exit
		3.7	2.3	K5	P.34-89	Eastbound entrance
	Kağıthane	4.4	2.7	K6	Hasdal-Okmeydanı connector — O-2
		4.5	2.8	K7	Darülaceze Cd.	Eastbound entrance
		6.5	4.0	K8	Piyalepaşa Blv.
	Şişli	8.3	5.2	K9	Büyükdere Cd.	Eastbound exit via K8
		9.4	5.8	K10	Barbaros Blv.
	Beşiktaş	10.7	6.6	K11	Barbaros Blv.	Eastbound entrance and westbound exit
	Bosphorus	11.8	7.3	Bosphorus Bridge (₺8.50 toll)
	Üsküdar	13.8	8.6	K12	Beylerbeyi Kavşağı
		15.2	9.4	K13	Şile Motorway — O-2
		16.0	9.9	K14	Acıbadem Cd.	Eastbound exit
		16.9	10.5	K15	O-4 — O-2, Kocaeli, Ankara	Eastbound exit, westbound entrance and exit
		18.4	11.4	K16	D.100 — Gürbulak
	Kadıköy	19.9	12.4	K17	F. Kerim Gökay Cd.	Eastbound exit and westbound entrance
		20.5	12.7	-	Bağdat Cd.	Trumpet interchange
1.000 mi = 1.609 km; 1.000 km = 0.621 mi       Incomplete access        Tolled