Balloon loop


Balloon loop at Linnéplatsen at the tramway in Gothenburg, Sweden.
Double sided island platform on a balloon loop - Olympic Park, Sydney, Australia
P1 & P4 departures
P2 & P3 arrivals
Maules Creek & Boggabri Coal Terminal East balloon loops

A balloon loop, turning loop or reversing loop (North American) allows a rail vehicle or train to reverse direction without having to shunt or even stop. Balloon loops can be useful for passenger trains and unit freight trains such as coal trains.

Balloon loops are common on tram or streetcar systems. Many streetcar and tram systems use single-ended vehicles that have doors on only one side and controls at only one end, or they haul trailers with no controls in the rear car and so must be turned at each end of the route.


Balloon loops were first introduced on tram and, later, metro lines. They did not commonly appear on freight railways until the 1960s, when the modernising British Rail system introduced merry-go-round (MGR) coal trains that operated from mines to power stations and back again without shunting.[citation needed]


Light-rail train using the balloon loop at Lechmere station in Cambridge, Massachusetts USA in 2020

Balloon loops enable higher line capacity (faster turnaround of a larger number of trams) and allow the use of single-ended trams which have several advantages, including lower cost and more seating when doors are on one side only. However, double-ended trams also benefit from the capacity advantage of balloon loops, for example on the former Sydney tram system where loops were used from 1881 until the second-generation system's closure in 1961. Initially the Sydney system was operated by single-ended steam trams and then, from the 1890s, by double-ended electric trams. Lines were looped in the Sydney CBD and the other busiest areas of operation, such as the eastern suburbs lines, as they provided greater turn-around capacity on this very busy system. The Sydney system was the first example of a tramway system using loops and has continued to build them up to 1997 (third-generation system).

Later in the 19th century, looped streetcar (tram) lines also began to appear on systems in the US and soon looped operation with single-ended streetcars became widely used on many North American streetcar systems. European systems were almost universally converted to looped operation in the early 20th century, and most also adopted single-ended trams. Loops were also used on some tramways in Asia, South America and New Zealand, as well as on some other Australian systems in addition to Sydney. Looped operation with single-ended trams is still the predominant method of tramway operation in the world, in spite of the recent construction of some new, typically smaller, stubbed systems with double-ended trams.



South Ferry balloon loop

On a balloon loop, the station is on the balloon loop, and the platform may be either curved or straight.



The tram systems in Vienna, Graz, Linz and Innsbruck employ Balloon Loops


France (Paris Métro)

United Kingdom

Simplified rail network around Newcastle
Heaton Depot
closed 1980
Manors Tyne and Wear Metro
Carliol Square
closed 1850
Tyne Valley line via Scotswood  
Newcastle Central Tyne and Wear Metro

United States

Lower level (suburban)
Upper level (mainline)
Grand Central Terminal track layouts, showing dual-level balloon loops


  • Various stations of the Hong Kong Tramways and MTR Light Rail
  • The Charleroi Pre-metro system features two balloon loops, at Beaux-Arts and Waterloo stations. This map is not current. Since 2013 there is a new connection between Sud and Park.
    In the Charleroi Pre-metro, both the Beaux-Arts and Waterloo stations have balloon loops. At Beaux-arts, trains between Sud and Anderlues (line M1&M2, both directions) first run through the station on a platformless track, take the underground balloon loop then stop at the platform leading to their destination. Waterloo station service four lines (M1,2,3,4) going to three directions, on a single island platform. Trains from Gilly station either diverge to the right and end up at the station to continue to Parc station, or diverge to the left to end up on the other end of the island platform to go towards Beaux-Arts. At the station is also a bypass so trains can run from Gilly directly to Beaux-Arts, without halting at the platform. No scheduled trains thus fully run the loop (or the bypass).
  • The Amsterdam, Rotterdam and The Hague tram systems have balloon loops at the end of nearly all lines. Amsterdam line 5 terminus at Amstelveen Binnenhof[6] and The Hague lines branded as Randstadrail do not have balloon loops.(RandstadRail 4 and extra service 34 started to use turning loops later)(only in The Hague)
    Across these cities there are several unused balloon loops that were in use until lines were extended or abolished. These loops however are still maintained for eventual purposes. But some have been removed.
    The municipality of The Hague however plans on removing them and purchase new trams with a drivers cabin on both sides of the tram. (New trams have long since been installed and a number of turning loops have been removed) The new extension of the Utrecht Express tram has a loop at De Uithof.
  • The Saitama New Shuttle has a balloon loop at Ōmiya.

Multiple stations on a balloon loop:

With balloon loop: The balloon loop is past the station.

Brooklyn Bridge and City Hall stations in New York City.
  • Bad Herrenalb, Albtalbahn, Germany: the train passes the loop before arrival
  • Bowling Green on New York City's IRT Lexington Avenue subway line is the southern terminus for 5 service in the evenings & on weekends, with the South Ferry inner loop (see previous section) used to turn trains.
  • Brooklyn Bridge – City Hall, also on New York City's IRT Lexington Avenue Line, is the southern terminus for Lexington Avenue local service (the 6 and <6> trains), with the City Hall loop (see previous section) used to turn trains.
  • Howard Station on the CTA Red Line in Chicago uses a balloon loop to turn a northbound train back south. Because the other end of the line does not contain a loop, the wear on the wheels is evened out after two trips.
  • The Irish Steam Preservation Society's line at Stradbally, Co.Laois, Ireland consists of a balloon loop: trains operate from the station and back again via the loop.
  • 69th Street Terminal, the western terminus of the SEPTA Market–Frankford Line in Philadelphia: westbound trains discharge passengers at the platform and go around the loop to one of two eastbound platforms to pick up passengers.
  • Gateway Center in Pittsburgh used to be the north/west end of the Pittsburgh Light Rail line. Westbound trains would discharge passengers at the inbound platform, then go around a loop to the outbound platform to pick up passengers. When the subway was extended in 2009–2012, the loop was removed; while the original outbound platform under Liberty Ave was left intact, the inbound platform was demolished and moved.
  • Kennington tube station, on the London Underground's Northern line: trains from the Charing Cross branch can terminate at Kennington and then run around a loop to return north. Trains from the Bank branch cannot use this loop.
  • Schwabstraße station on the Stuttgart S-Bahn: the loop is south of the station and completely underground
  • Tonnelle Avenue (HBLR station): the loop is to the west of the station.

Tram systems

Balloon loops are used extensively on tramway systems with single-ended trams. Usually located at termini, the loop may be a single one-way track round a block. Single-ended trams have a cab at only one end and doors on one side, making them cheaper and having more space for passengers. On tram systems with double-ended trams balloon loops are not required but may still be used as they can provide greater turn-around capacity than a stub terminus; the Birmingham Corporation Tramways terminus at Rednal had a balloon loop in addition to the conventional stub tracks, providing extra capacity to handle weekend and bank holiday crowds visiting the nearby Lickey Hills. The Milan interurban tramway network, although using double-ended trams, had balloon loops at termini within the city limits so that they could be used as backup termini by the single directional trams used on urban service. Another example is in Potsdam, Germany.




Loading loops

New South Wales
  • Coal
    • Camberwell: Coal
    • Craven: Coal
    • Fassifern: Coal - has triangle as well, so trains can go north or south
    • Gunnedah: Coal
    • Boggabri Coal
    • Maules Creek
    • Boggabri Coal Terminal East
    • Mount Thorley: and other mines - coal
    • Newdell Junction: Coal - has two balloon loops for different coal mines
    • Newnes Junction coal loader
    • Tahmoor: Coal - due to change in operational requirements, the balloon loop now points the wrong way, and requires trains to be top and tailed.
    • Ulan: Coal
    • Wilpinyong: Coal
  • Wheat
    • Penny Road, near Moree: Wheat
  • Owanilla, Maryborough South;[9] includes a circle inside the balloon to allow inspection before unloading/loading![10]
South Australia
Western Australia
  • Koolyanobbin East (iron ore)[14]

Unloading loops

New South Wales
  • Eraring - power station
  • Vales Point: power station ; Coal unloader
  • Port Waratah: Coal & Wheat unloader at port
  • Koorang Island: Coal unloader at port
  • Port Kembla - coal and wheat
South Australia
West Australia
  • Yarrie: Iron ore[17]
  • Koolyanobbing: Iron Ore
  • Pinjarra: Alumina[18]
  • Kwinana: N/A[18]
  • Bunbury: N/A[18]



  • Selke Valley Railway (German: Selketalbahn): Part of the 1,000 mm (3 ft 3+38 in) gauge Harz Narrow Gauge Railways (German: Harzer Schmalspurbahnen). A balloon loop has been constructed at Stiege to allow freight trains between Nordhausen and the power station at Silberhütte (Harzgerode) to make their journeys without the locomotive having to run round. Passenger trains continue along the branch beyond Stiege to Hasselfelde where they reverse.


Has several balloon loops and triangles.

New Zealand

United Kingdom

There are several balloon loops at power stations in the UK; these have been provided so that coal trains may unload without stopping (known as the merry-go-round system). Examples include Cottam, Didcot, Drax, Eggborough, Ferrybridge, and Ratcliffe-on-Soar.

Also, the Fife Circle line between Edinburgh and the county of Fife acts like a giant balloon loop, branching off after Inverkeithing and connecting again at Kirkcaldy.

Also, two London Underground lines have balloon loops; the Northern Line has one at Kennington, where trains can terminate, drive around the reversing loop, and then start again whilst others can pass through; whereas the Piccadilly Line has one serving Terminal 4 of Heathrow Airport (half of all trains use this loop to return eastwards back into London, while trains terminating at Terminal 5 must halt and reverse).

United States


Both the French and the British terminals of the Eurotunnel Shuttle service through the Channel Tunnel consist of balloon loops, in opposite directions to even out wear on the wheels.

Occasionally, balloon loops are used for reversing trains on lines with heavy grades and tight curves to equalise wear on both sides of locomotives and rollingstock. Such a balloon loop was constructed at Beech Forest on the 2 ft 6 in (762 mm) Victorian Railways line from Colac to Crowes.


Advantages of a balloon loop include:

  • Smooth operation
  • Trains can arrive in any free platform, while another train is leaving any platform.
  • Reversal of rolling stock helps even out wear and tear on the wheels.
  • Eliminates need for brake test if locomotives uncoupled to carry out run around move.

Compared to stations with stub platforms, balloon loops allow:

  • Fewer tracks and platforms are required
  • Arrivals into some platforms do not block departures from other platforms
  • Time is not lost while drivers change ends and reset the train for the other direction
  • If the driver changed ends and discovers a hidden fault, then delays to trains are less likely


Disadvantages of a balloon loop include:

  • Very space consuming.
  • The sharp curves cause noise, as well as wear on wheels and rails.
  • If the platform is located on the curve, the gap between the platform and railcar door is a hazard.
  • On systems where, for reasons of economy, the couplings are made non-reversible (e.g. by fitting the air brake pipe along one side of the car only), the use of a balloon loop will cause a proportion of the rolling stock to face the "wrong" way and it may not be possible to assemble a complete train in a depot, even if sufficient cars are on hand. This was the case on the Charing Cross, Euston and Hampstead Railway (now part of the Northern line of London Underground).


  • On many systems with a balloon loop the couplings and brake hoses are made reversible.
  • At coal ports such as Kooragang in Newcastle, New South Wales the space inside the balloon loops is used for storing coal, so that it is not wasted.
  • At the Olympic Park station in Sydney, the loop is flattened where the platforms are located, so that the platform faces are straight.
  • After the opening of a loop at Charing Cross (Embankment) in 1914 (replaced in 1926 by the present Kennington loop) car ends were marked "A" or "B" (later, when axles were designated by letters, the "B" car ends became "D" to match the adjacent axle), and it was not permitted to couple cars together if the ends to be coupled bore the same letter. It was found necessary to provide a turntable at Golders Green depot (near the other end of the line), for use when there was an imbalance of car directions.[21]
  • The former South Ferry station on the New York City Subway solved the railcar door hazard by using gap fillers that extended out to the railcar door when the train triggered a switch on the tracks. The older station had been closed, but was reopened as a result of damage to the newer station caused by Hurricane Sandy.


  1. ^ 5 Southern & TfL (Map) (3rd ed.). Railway Track Diagrams. Cartography by John Yonge. Trackmaps. November 2008. p. 18 Romney, Hythe & Dymchurch Railway. E inset. ISBN 978-0-9549866-4-3.
  2. ^ "Paulsboro - The New Omniport" (video). South Jersey Port Corporation.
  3. ^ "Home". The Wellston Loop. Retrieved 2019-06-16.
  4. ^ "Truckee Donner Railroad Society". Archived from the original on 2012-07-11. Retrieved 2012-05-01.
  5. ^ "MTA Capital Construction - South Ferry Terminal Project".
  6. ^ "Network plans and maps".
  7. ^ 5 Southern & TfL (Map) (3rd ed.). Railway Track Diagrams. Cartography by John Yonge. Trackmaps. November 2008. p. 43 Piccadilly line: South Harrow & Heathrow - Acton Town. D inset. ISBN 978-0-9549866-4-3.
  8. ^ 4 Midlands & North West (Map) (2nd ed.). Railway Track Diagrams. Cartography by John Yonge. Trackmaps. March 2005. p. 40 Hunts Cross - Moorfields. ISBN 0-9549866-0-1.
  9. ^ Railway Digest. October 2014. p. 14. Missing or empty |title= (help)
  10. ^ "Owanilla Balloon Loop". Railpage.
  11. ^ Railway Digest. February 2013. p. 54. Missing or empty |title= (help)
  12. ^ "Map: Standard gauge track Northgate-Wirrida" (PDF). Archived from the original (PDF) on 2016-03-04. Retrieved 2015-02-02.
  13. ^ "Map: Standard gauge track Crystal Brook" (PDF). SA Track and Signal.
  14. ^ "Map: Standard gauge track Koolyanobbing East-Koolyanobbing" (PDF). SA Track and Signal.
  15. ^ "Balloon loop". Archived from the original on 2013-12-03.
  16. ^ "Grain Loop". Rail Geelong. Retrieved 2013-12-28.
  17. ^ "Australia Map Directory of Western Australia WA of". Archived from the original on 2011-06-11. Retrieved 2010-08-04.
  18. ^ a b c Railway Digest. October 2014. p. 38. Missing or empty |title= (help)
  19. ^ " - african-minerals Resources and Information". Archived from the original on 2014-03-28. Retrieved 2014-03-28.
  20. ^ "Dimbokro - MapQuest".
  21. ^ Bruce, J. Graeme (1988). "7. The First of the Standard Tube Stock 1923/25". The London Underground Tube Stock. Shepperton: Ian Allan. pp. 56–57. ISBN 0-7110-1707-7.

External links

  • Media related to Rail track loops at Wikimedia Commons