Main line balloon loops

[bahnause]

Thanks everyone!

The loop is also regularly used to turn a train round when the first class is on the wrong side.

 

[D6130]

There is a balloon loop at the end of Bologna San Donato marshalling yet in Italy....which is nowadays used as a test circuit for new and recently-overhauled locomotives and units (cf Velim, Czechia).

 

[MarcVD]

There on one on the light metro of Charleroi.

 

[ricohallo]

Not sure if it counts but Brussels Airport is kind of used as one. Trains come in from Brussels and then continue without reversing to go back towards Brussels. They are usually advertised as terminating at Brussels Airport where they change into a service that goes out on the other side.

 

[DanielB]

Believe it was written earlier that a loop with multiple stations didn't count. Otherwise you could consider Gouda-Den Haag HS-Schiedam-Gouda as a loop as well

 

[43096]

There on one on the light metro of Charleroi.

View attachment 211818

Which is not “main line”, which was the exam question.

 

[ricohallo]

Believe it was written earlier that a loop with multiple stations didn't count. Otherwise you could consider Gouda-Den Haag HS-Schiedam-Gouda as a loop as well

Yes, though it is not used as such in regular passenger service.

 

[D6700]

Ceska Trebova in the Czech Republic has one, which I once travelled over on a railtour a good few years ago, taking us from the back of the station to a platform road without reversing.

Whilst more niche, the inner circuit at the Velim test track in the Czech Republic includes such a loop.

Stratford in East London also has such a layout to/from Temple Mills, which is made use of by some Orient Way ECS moves.

 

[The Pelican]

Stratford in East London also has such a layout to/from Temple Mills, which is made use of by some Orient Way ECS moves.

The Stratford one has led to the interesting layout of the Overground North London line, the Greater Anglia Stratford-Tottenham Hale line, and the two DLR tracks of the Stratford International-Canning town branch. The first and last of these used to be the platforms for the Dalston-Woolwich section of the North London Line.

 

[edwin_m]

It used to be possible to continue straight on at Spondon and enter Derby station from the north via Chaddesden Sidings, and this route was used to avoid reversal for trains continuing to/from the Crewe or Birmingham lines in the pre-DMU days. I don't know if it was routinely used to send any trains back via Spondon.

 

[beardedbrit]

in Boston, the Blue Line has an underground loop at the Bowdoin terminus

 

[43096]

in Boston, the Blue Line has an underground loop at the Bowdoin terminus

Which doesn't count against the OP's criteria as it is not main line.

 

[izvor]

Stiege on the Harz narrow gauge, still there I believe?

 

[Springs Branch]

If we are considering metro systems, then surely Chicago's L must have the most impressive Loop of all, although I grant you it isn't exactly balloon-shaped.

in Boston, the Blue Line has an underground loop at the Bowdoin terminus

If we're allowed US "heavy" metro (as opposed to light rail or tramway/streetcar), then I'll give an honourable mention to two interesting examples on the New York Subway.

1) The City Hall Loop on the Lexington Ave line, which allows downtown 6-Trains terminating at Brooklyn Bridge–City Hall to reverse direction and return uptown towards the Bronx.

The loop is interesting because of the closed but ornate City Hall Station along the way. Passengers ("riders" in local parlance) are technically not allowed on empty trains around the loop but allegedly, with a sympathetic or unobservant conductor, it's sometimes possible to get a passing view of the dimly-lit, decorative City Hall platform.


2) The South Ferry loops. There are still two parallel balloon loops here, although two new straight dead-end platforms have now been constructed at a lower level to terminate all regular 1-Trains. The original "outer loop" is still available for operational purposes when needed, but the original sharply curved platform on the loop is closed.

The parallel "inner loop" is still in use evenings and all weekend to reverse Lexington Ave 5-Trains which currently terminate at Bowling Green station at these times.

Image shows track arrangement at South Ferry balloon loop (before construction of new low-level terminal platforms)
Source: Wikimedia. Public Domain.

The old South Ferry station was interesting for the mechanical gap-fillers, which were necessary with the platform being built on a very sharp curve, the fact that only half the train would fit into the station (necessitating walk-throughs if you were in the back half) and the station's old-school "Noo Yawk Subway" ambience.

Flange squeal from the tight curvatures here made for an ear-piercing, deafening situation on the old South Ferry platform (in an already raucous NY Subway environment) if a West Side train was departing while an empty East Side train was passing through at the same time.

Image shows a train in the original sharply-curved platform at South Ferry with gap-filler mechanisms.
Source: Marc A. Hermann / MTA New York City Transit on Wikimedia. Licensed under the Creative Commons Attribution 2.0 Generic license.

Melbourne, Sydney, Liverpool and, since very recently Auckland all have loops under their city centres . . .

Also in Australia:-

• Sydney Trains also have a balloon loop with a single station out in the suburbs at Olympic Park Station.
  
  During events at the adjacent stadium, through trains run to and from major destinations around Sydney and use all of the station's four platforms. Outside major events, there's a regular shuttle train on the short branch to or from nearby Lidcombe for connections to main line services, and empty platforms at Olympic Park are used to stable empty trains between the peaks.
  
  
• Adelaide's suburban rail system used to have a single track / single platform terminus on a balloon loop at Outer Harbor. The line looped around the circumference of a local golf course. The balloon loop was decommissioned when the last few kms of the double-track Outer Harbor line were singled (maybe in the 1990s?), and the terminus became a simple in-and-out single line terminus.