Circle Line

Circle Line
Stadium MRT Station
Stadium MRT Station
Type Medium-capacity rail
Station Count 30 (Operational)
3 (Under Construction)
Line length 35.5 km (Operational)
4 km (Under Construction)
Termini Dhoby Ghaut
Marina Bay
Depot Kim Chuan Depot
Operational Data
Operators SMRT Trains
Rolling stock Alstom Metropolis C830
Alstom Metropolis C830C
Alstom Metropolis C851E
Electrification 750 V DC third rail
Track gauge Standard Gauge (1435mm)
Opened 28 May 2009 (Stage 3)
17 Apr 2010 (Stage 1 & 2)
08 Oct 2011 (Stage 4 & 5)
14 Jan 2012 (CCLe)
Year 2026 (Stage 6)

The Circle Line (CCL) is an underground, driverless, medium-capacity MRT line and the fourth rail line in Singapore, running an orbital route through residential areas and linking all radial routes leading to the city. The line is currently 35.5 km long with 30 stations, running from Dhoby Ghaut (CC1) to HarbourFront (CC29) via Serangoon. A separate branch line known as the Circle Line Extension links Promenade (CC4) to Marina Bay (CE2) via Bayfront (CE1).

The line is also the first medium-capacity rail line in Singapore, with trains operating in a three-car formation, half as long as the usual six-car formation used on previous lines. The rolling stock is based out of Kim Chuan Depot, touted as the largest fully-underground train depot in the world.

A line extension under construction, ‘Circle Line Stage 6‘ will complete the Circle Line, closing the circular route between HarbourFront and Marina Bay with 3 additional stations and is scheduled for completion in 2026.

Timeline & History

  • 28 May 2009: Opening of Circle Line Stage 3, with trains running between Bartley and Marymount stations
  • 17 Apr 2010: Opening of Circle Line Stages 1 & 2, with trains running between Dhoby Ghaut and Marymount stations
  • 8 Oct 2011: Opening of Circle Line Stages 4 & 5, with trains running between Dhoby Ghaut and HarbourFront stations
  • 14 Jan 2012: Opening of Circle Line Extension, connecting Promenade to Marina Bay via Bayfront

The Circle Line was planned as an orbital line linking all existing rail lines, allowing commuters to transfer between rail lines while avoiding the city centre, with interchanges at Paya Lebar, Serangoon, Bishan and Buona Vista. The southern reaches of the line would connect to the City centre. Construction work began in 2002-2003 and the line was constructed in 5 stages, along with Kim Chuan Depot, a fully underground train depot providing maintenance and stabling facilities for the Circle Line running stock.

Originally scheduled to open progressively from 2006 till 2010, the Nicoll Highway collapse of 2004 delayed the opening of Stages 1 and 2, resulting in the unaffected Stage 3 opening for revenue service first on 28 May 2009. A new Nicoll Highway station, two-thirds the size of the original station, was built a short distance away from the old station. Stages 1 and 2 eventually opened on 17 Apr 2010, opening up new connections to the Bras Basah and Marina Centre area.

Stages 4 & 5 opened a year later, on 8 Oct 2011, bringing the line to HarbourFront. Caldecott and Haw Par Villa stations, previously planned as shell stations, were built as normal stations and opened along with the rest of the line. That left Bukit Brown as the only remaining shell station on the Circle Line, awaiting future developments in the Bukit Brown area. Presently, its facilities are used as emergency escape shafts.


Operational Stations

The station code CC18 is reserved for a future infill station at Bukit Brown.

Circle Line Stage 6 stations (by Year 2026):
Future Station:

Currently a shell station, expected to open with the further development of Bukit Brown.

Station Code Change for Circle Line Stage 6

In the Future Network Map (March 2020 version) by the Land Transport Authority, the station codes for both Bayfront and Marina Bay are indicated as CC34DT16 and CC33NS27TE20 respectively, indicating that the new station codes will take effect after the opening of the Circle Line Stage 6.

Rolling Stock

The Circle Line uses electric multiple unit (EMU) trains operating in a three-car configuration, with four doors per side on each carriage.

Train Quantity Entered Service Manufacturer Built at
Alstom Metropolis C830 40 May 2009 Alstom Valenciennes, France
Alstom Metropolis C830C 24 June 2015 Shanghai Alstom Transport Shanghai, China
Alstom Metropolis C851E (CCL) 23 TBA Alstom Barcelona, Spain

Alstom Metropolis C830 trainsets were the first generation of trains to serve the Circle Line. A total of 40 trainsets were ordered as part of turnkey Contract C830, with four doors per side, and are stabled at Kim Chuan Depot. They are built in France by Alstom between 2006–2008.

Shanghai Alstom Metropolis C830C trainsets were ordered to increase the capacity of the Circle Line. A total of 24 trainsets were ordered, as part of Contract C830C, and are also stabled at Kim Chuan Depot. Largely similar in design to their C830 cousins, these trains are built in China by Shanghai Alstom Transport Co. Ltd., a joint venture between Alstom and Shanghai Electric, between 2014–2015.

Alstom Metropolis C851E trainsets were ordered to increase the capacity of the Circle Line ahead of the opening of the Circle Line Stage 6. A total of 23 trainsets were ordered, with trains manufactured and assembled by Alstom in Barcelona, Spain.

Train Control

The Circle Line is equipped with the Alstom Urbalis 300 Communications-based train control (CBTC) signalling system. Trains operate fully automatically (GoA level 4; unattended train operation), but SMRT Trains elects to have a train attendant onboard in case of emergencies.

Construction Incidents

  • Nicoll Highway Collapse – see CC5 Nicoll Highway
  • Acquiring of Hock Kee House – see CC9EW8 Paya Lebar
  • Cornwall Gardens cave-in – In May 2008, tunnelling work caused an 8m by 7m stretch of Cornwall Gardens to sink into a 3m crater. No one was injured nor were homes damaged, but water and telecommunication links to three homes were cut off

Circle Line 6 Upgrades

In preparation for the opening of Circle Line Stage 6 in 2026, LTA and SMRT have embarked on a series of system enhancements to the existing Circle Line (as of July 2019).

These upgrades include:

  • Signalling System
  • Power Supply System
  • Hardware and software of the communications system and the integrated supervisory control system (ISCS)


Back to Trains