Outer Circular Highway OCH runs from Kottawa to Kadawatha.

At southern end of Outer Circular Highway is located at Kottawa on Colombo-Ratnapura-Wellawaya-Batticaloa road  (A4 – Highlevel Road) where Southern Expressway meets OCH. The northern end of the highway is located at Kadawatha on Kandy Road or Colombo-Kandy (A1) road.

The OCH is a 4-lane Highway, and the maximum speed of the Highway is 100 kmph.

Interchanges

This road has Kottawa (Colombo) Entrance and four Interchanges.

• Kottawa Entrance

The starting point t of the Southern Expressway (E01) which connects with the Outer Circular Highway. Located at Kottawa along High Level Road.

Kottawa (1.8 km), Maharagama (6.3 km), Nugegoda (11.3 km), Colombo (20.6 km), Ratnapura (79.1 km), Avissawella (37 km), Homagama (2.2 km)

• Athurugiriya Interchange

  Located between Malabe and Athurugiriya on Kotte-Bope Road (B240).

Main Bus routes accessible from the Interchange
Route No 190 – Meegoda – Pettah

• Kothalawala Interchange

Located between Kaduwela and Malabe on New Kandy Road (B263).

Main Bus routes accessible from the Interchange
Route No 177 – Kaduwela – Kollupitiya
Route No 17 – Panadura – Kurunegala/ Kandy

• Kaduwela Interchange

Located in Colombo-Hanwella Low Level Road (AB10) – (Kadawatha Direction Exit and Matara Direction Entrance) and  Biyagama Road(B214) – (Kadawatha Direction Entrance and Matara Direction Exit).

Main Bus routes accessible from the Interchange
Route No 143 – Hanwella – Pettah(Colombo-Hanwella Low Level Road)
Route No 148 – Labugama – Pettah(Colombo-Hanwella Low Level Road)
Route No 228 – Weliweriya – Pettah(Biyagama Road)
Route No 225 – Kirindiwela – Pettah(Biyagama Road)
Route No 224 – Pugoda – Pettah(Biyagama Road)

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  Kadawatha Interchange

Located between Kadawatha and Eldeniya on Kandy Road (A1).
Main Bus routes accessible from the Interchange
Route No 200 – Gampaha – Pettah
Route No 180 – Nittabuwa – Pettah

Outer Circular Highway Map

For More details – Visit RDA Expressway website:
http://www.exway.rda.gov.lk/index.php?page=expressway_network/e02

Tariff Schedule

Entering vehicles to the expressway will have to pay a certain fee for usage. The toll will be charged based on the number of kilometers intended for travel and the category of vehicle. Charges levied for all four category of vehicles.

Highway and Expressway Road Network Map of Sri Lanka by Road Development Authority