# Stackabouts of the world, unite!



## Ryme Intrinseca (Aug 3, 2016)

The three-level roundabout, or 'stackabout', is an interchange consisting of two mainlines with a large roundabout on a third level, which handles turning movements. It is very similar to a three-level diamond or 'volleyball' interchange, but uses a single large roundabout instead of a series of signalized intersections.

This design is most associated with the UK, which has 27 by my count, but they are also used in many other countries. Some examples are below:

1. UK Google Maps
2. Italy Google Maps
3. Belgium Google Maps
4. The Netherlands Google Maps
5. United States Google Maps
6. Spain Google Maps
7. France Google Maps
8. Czech Republic Google Maps
9. Austria Google Maps
10. Qatar Google Maps
11. China Google Maps
12. Norway Google Maps
13. Malaysia Google Maps
14. Latvia Google Maps
15. Lithuania Google Maps
16. Greece Google Maps
17. Slovakia Google Maps
18. Ukraine Google Maps
19. Kuwait Google Maps
20. Ireland Google Maps
21. Sweden (under construction)
22. Bulgaria Google Maps
23. Russia Google Maps
24. Mexico Google Maps
25. Portugal Google Maps
26. Tajikistan Google Maps
27. Uzbekistan Google Maps
28. Libya Google Maps
29. Singapore Google Maps
30. Vietnam Google Maps

Do you know of any other country that uses this design?


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## patakcze (Jul 9, 2012)

Some more in the Czech Republic:
https://goo.gl/maps/bpet4y9ZveT2 finished, but not in use yet
https://goo.gl/maps/SoqaPsmfNCr
https://goo.gl/maps/cvjCMaZFzuJ2


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## Kemo (Jan 22, 2012)

Does this count? https://www.google.pl/maps/@50.0872531,19.8916612,294m/data=!3m1!1e3


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## Ryme Intrinseca (Aug 3, 2016)

Kemo said:


> Does this count? https://www.google.pl/maps/@50.0872531,19.8916612,294m/data=!3m1!1e3


I'd say it's more like a three-level diamond.


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## Highway89 (Feb 19, 2015)

A-66/EX-A1 interchange in Spain:
https://www.google.co.uk/maps/@39.9812723,-6.152443,542m/data=!3m1!1e3


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## italystf (Aug 2, 2011)

I/C between SS13 and RA16/SR177 near Pordenone, Italy
https://www.google.it/maps/@45.9460813,12.7202797,18z


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## gr_kanev (Mar 14, 2013)

Does this count ?
https://goo.gl/maps/RRB8dDJ11zE2
Bulgaria


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## rakcancer (Sep 2, 2010)

Believe it or not. This one is from USA (if it counts):
https://www.google.com/maps/@38.8990023,-77.0536088,322m/data=!3m1!1e3?hl=en

and one more:
https://www.google.com/maps/@38.9024785,-77.0494532,384m/data=!3m1!1e3?hl=en


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## Ryme Intrinseca (Aug 3, 2016)

Looks like those Bulgarian and American examples are only on two levels, though there is a US three-level roubdabout in the OP.


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## Verso (Jun 5, 2006)

^^ The Bulgarian example seems to be on three levels.


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## Kanadzie (Jan 3, 2014)

rakcancer said:


> Believe it or not. This one is from USA (if it counts):


Washington DC is a really strange place to drive. If you are driving and the car is moving, you're probably going in a circle, loop, roundabout, ellipsoidal road of any forms :lol:


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## Ryme Intrinseca (Aug 3, 2016)

Verso said:


> ^^ The Bulgarian example seems to be on three levels.


It looks like three levels but if you zoom in you can see it's actually two - one of the 'levels' is actually just a cut through at the same level as the roundabout (presumably signalized). At least according to Google's mapping, anyway.


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## gr_kanev (Mar 14, 2013)

According to Google's mapping it may look like even one level.
Here's short video, that shows it's three level.




And one picture :








Level "-1" is N-NE -> S-SW; the roundabout is on level "0", level "+1" is NW-SE.

One more better video (start watching from 1:09) :
































First one minute


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## Ryme Intrinseca (Aug 3, 2016)

Looks like we have

22. Bulgaria


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## Exethalion (Dec 23, 2008)

Where do we draw the line between a signalized stackabout and a three level diamond? Numerous more world examples can be drawn if we do not exclude the latter.


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## Ryme Intrinseca (Aug 3, 2016)

Exethalion said:


> Where do we draw the line between a signalized stackabout and a three level diamond? Numerous more world examples can be drawn if we do not exclude the latter.


It's a good question. I think intuitively there is a difference, which comes down to a variety of factors:

1) Stackabout geometry is typically circular or oval shaped rather than square or rectangular.
2) Stackabouts typically separate entry and exit points from each other, whereas a three-level diamond typically has entry and exit points meeting each other at four-way intersections.
3) Stackabouts are typically designed without signals (even if they are added later).

Of course, there are borderline cases, like the example in Bratislava, which you could argue is both a stackabout and three-level diamond! https://www.google.co.uk/maps/@48.1416238,17.1515485,18z


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## Exethalion (Dec 23, 2008)

Bratislava ring road is quite the exciting stretch of motorway it seems. I like the 450 degree exit ramp a few miles to the north east of the stackabout-diamond.


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## dars-dm (Oct 13, 2007)

Russia, near Moscow
https://www.google.ru/maps/@55.6609093,37.2230572,349m/data=!3m1!1e3


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## verfmeer (Jul 30, 2014)

What about this 6-way Stackabout with extra fly-overs in the Netherlands?


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## Ryme Intrinseca (Aug 3, 2016)

Knooppunt Kleinpolderplein is more like a five-level roundabout 


dars-dm said:


> Russia, near Moscow
> https://www.google.ru/maps/@55.6609093,37.2230572,349m/data=!3m1!1e3


And we have:

23. Russia


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## sponge_bob (Aug 11, 2013)

Ireland is _finally_ joining the 3 Level Stack party in *2017* when the *M6/M17/M18* Stack opens in Rathmorrissy near Galway. Photo in the last 2 months. 










From user M17 on Boards.ie

No more planned.


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## metasmurf (Nov 16, 2007)

I don't know if this qualifies. The road is not clasified as motorway, but it has this sign:










It's Riksvei 706 in Trondheim, Norway









Image source: https://reinertsenas.wordpress.com/2014/06/24/strindheimtunnelen-apner/


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## Ryme Intrinseca (Aug 3, 2016)

The Trondheim example looks like a regular two-level roundabout. There is a three-level roundabout outside Oslo though (see OP).


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## aswnl (Jun 6, 2004)

Ryme Intrinseca said:


> 3) Stackabouts are typically designed without signals (even if they are added later).


Perhaps in the UK. The Dutch example of the Rottepolderplein has had traffic lights since it opened in 1974. However the 3rd level was only added in 1981...


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## Ryme Intrinseca (Aug 3, 2016)

aswnl said:


> Perhaps in the UK. The Dutch example of the Rottepolderplein has had traffic lights since it opened in 1974. However the 3rd level was only added in 1981...


Hence 'typically'  I wouldn't be surprised if one or two of the UK examples were signalized from the outset too. There's still something of a contrast with three-level diamonds, which are usually signalized from day 1.


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## metasmurf (Nov 16, 2007)

Ryme Intrinseca said:


> The Trondheim example looks like a regular two-level roundabout. There is a three-level roundabout outside Oslo though (see OP).


Nah mate it's three levels. Look at the map.


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## Verso (Jun 5, 2006)

^^ It's two roundabouts one over another.


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## Ryme Intrinseca (Aug 3, 2016)

metasmurf said:


> Nah mate it's three levels. Look at the map.


I was looking at it as a two-level roundabout with another roundabout on top of it. It's certainly not a three-level roundabout though I suppose you could call it three-level roundabout*s*


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## Stavros86 (Jun 12, 2010)

*USA I-395 and Seminary Rd (SR 420) in Northern Virginia*
[38.829928, -77.113391]


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## KIWIKAAS (May 13, 2003)

Australia, Brisbane ''squareabout'

https://www.google.nl/maps/place/Br...2a35af3deaf40!8m2!3d-27.4697707!4d153.0251235'

https://www.google.nl/maps/@-27.503...4!1saORJ72DcYjUiK2aVOGFFXg!2e0!7i13312!8i6656


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## Exethalion (Dec 23, 2008)

metasmurf said:


> Nah mate it's three levels. Look at the map.


But its not a stackabout as there are not two unobstructed rights of way either under or over the roundabout.


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## Ryme Intrinseca (Aug 3, 2016)

Thanks to a tip from Chris Zwolle in another thread, we have:

24. Mexico

https://www.google.co.uk/maps/@19.0757655,-98.2878185,16z
https://www.google.co.uk/maps/@19.058728,-98.2787706,16z
https://www.google.co.uk/maps/@19.0101633,-98.2620089,16z


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## ElviS77 (Aug 3, 2007)

metasmurf said:


> It's Riksvei 706 in Trondheim, Norway


It's a very funny design, I don't think anyone outside of Norway would have considered it, but a proper stackabout it ain't---


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## MattiG (Feb 11, 2011)

ElviS77 said:


> It's a very funny design, I don't think anyone outside of Norway would have considered it, but a proper stackabout it ain't---


This does not qualify the criteria either, but there are some elements of stackabouts visible. It is the 6-way exit 43 on the 50/E18, Helsinki Ring 3. The E18 runs west-east (left-right) and the road 135 is the connection road to the Helsinki airport. One of biggest shopping centers in Finland lies just outside the image at the right-bottom corner.










It is kind of a "streched" stackabout where the roadabout part was pulled a few hundred meters to the north. There are some level crossings in place, but the traffic from and to the airport is free-flow. 

At the south end, the road 135 is at the level 3 (while the E18 being level 1 and the flyovers level 2). But at the roundabout, the road is at the level 1 below the flyovers. What is interesting, the flyovers cross the road 135 twice: above it at the roundabout, and below it at the spaghetti. 

https://www.google.fi/maps/@60.2975833,24.9629158,15.69z


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## sotavento (May 12, 2005)

^^ There are actually only 2 levels theres ... much of it is on the floor and there are 3 bridges over the main road. Nothing more.

Theres on in Lisbon (Portugal) but the bridges don't actually intersect each other since both form an Y

https://www.google.pl/maps/@38.763486,-9.1298687,443m/data=!3m1!1e3



Exethalion said:


> Where do we draw the line between a signalized stackabout and a three level diamond? Numerous more world examples can be drawn if we do not exclude the latter.



Having a roundabound vs. not having a roundabound ???



Over here there are hundreds of highway crossings with roundabounts over/under them but they never choose to produce a perfect stackabout ... or they sump one of the highways onto the roundabound or they depart completelly and create a bucket of noodles full of overly complex interchanges like this; (don't bother counting how many complicated routes there are)

https://www.google.co.uk/maps/@41.5562427,-8.4470457,13.29z


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## sotavento (May 12, 2005)

Exethalion said:


> Where do we draw the line between a signalized stackabout and a three level diamond? Numerous more world examples can be drawn if we do not exclude the latter.



Having a roundabound vs. not having a roundabound ???


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## triple-j (Aug 10, 2005)

Hope this counts. 
Kuala Lumpur, Malaysia. 
https://goo.gl/maps/YtXUv3PrN3v


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## marciomaco (Jan 17, 2009)

Portugal may enter on the list 

https://www.google.co.uk/maps/@41.5527505,-8.4067924,270m/data=!3m1!1e3


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## sponge_bob (Aug 11, 2013)

sponge_bob said:


> Ireland is _finally_ joining the 3 Level Stack party in *2017* when the *M6/M17/M18* Stack opens in Rathmorrissy near Galway. Photo in the last 2 months.
> 
> 
> 
> ...


User M17 on http://boards.ie/ posted an updated photo of the Rathmorrissy stackabout east of Galway a fortnight back. In service by end October 2017 I reckon. The M6 motorway runs underneath and is in service since 2010.


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## Tom958 (Apr 4, 2020)

In the US, there's a perfectly legitimate one in New Orleans: Google Maps


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