Are there developed countries in the world other than the U.S. which have "double cities"? (legally, light rail)

[dunno what to put here]

Yes, Liverpool and Manchester are very close and compete with each other for being the capital of North West England, but they are never referred to as 'Manchester and Liverpool' like 'Dallas and Fort Worth', they form separate metro areas.

[Trimac20]

Both the Sunshine Coast and Gold Coast aren't actually cities in the literal sense, although both are administered by city councils. The Sunshine Coast in particular is a collection of cities, each with it's own identity, clustered together. Think the Virginia Beach area.

There's also Kalgoorlie-Boulder, which is often actually listed in hyphenated form.

[OyCrumbler]

http://en.wikipedia.org/wiki/Twin_ci...ical_proximity)

[LindavG]

The whole area between Amsterdam, Rotterdam, the Hague and Utrecht is basically one big conglomeration (called the Randstad) with 7+ million people. If you travel by train you can get from Amsterdam to Rotterdam in 30 minutes, from Rotterdam to the Hague in 25 minutes, from the Hague to Utrecht in 35 minutes, etc.

[Average Fruit]

Originally Posted by BIMBAM

Hamilton and Toronto are a bit like that, although Toronto is significantly larger.

I think a better example would be Kitchener and Waterloo or even Ottawa and Gatineau

[FrankCostello]

Bratislava and Vienna are the closest capital cities in Europe and second closest in the world (not counting Rome and Vatican City) and quite easily commutable. Also, Maastricht, the Netherlands and Aachen, Germany are both relatively big cities and only few minutes away from each other.

[dunno what to put here]

My city, Leeds, is joined to another city, Bradford.. you can travel between the two without leaving urbanity.

[Proterra]

I guess Arnhem-Nijmegen in the Netherlands would be the best example... Metro area (third largest in NL after Randstad and Brabant) is about 0.8 million, cities are very close to each other in size (I believe Arnhem 150,000, and Nijmegen around 170,000 within city limits) and there are often also referred to as Arnhem-Nijmegen, where they are two seperate cities.

Mainz-Wiesbaden and Leipzig-Halle come to mind as well, but I doubt they're as much seen as true "twin cities" as Arnhem-Nijmegen are. Rotterdam-The Hague, also in the Netherlands would be another contender, as they share an urban area together, but still are part of a much larger conurbation which includes practically the whole of both Hollands. Then we have Gdańsk-Gdynia, which is officially referred to as "tri-city" because of the beach resort of Sopot being between the two, but there is a huge size difference between Gdańsk (450000) and Gdynia (270000) on one side and Sopot (40000) on the other. I believe Sopot isn't even the largest city in Trójmiasto, but number 5 or 6.

I suppose Athens-Piraeus could also be counted as a "twin city", but also here, there are suburbs of Athens which have a bigger population within the city limits than Piraeus does, and Athens is about 3-4 times as populous as Piraeus.

Then there is Leeds-Bradford, which has been mentioned before in this thread, which are both very close in size, very close in importance and very close in location, which is the closest one to a true "twin city" in the UK. Main thing it lacks in this regards is that it is not referred to as Leeds-Bradford in everyday usage, but people tend to refer to the two separate cities as separate entities. Manchester and Liverpool are very close, but it has other large cities in it's urban area which makes it more a conurbation than anything else, Warrington, for example is located about halfway between the two, and is roughly half the size of either Manchester or Liverpool. Birmingham-Coventry could qualify, but again, the size difference (B'ham - >1m, Coventry, 300K) makes it not a true "twin city" in my opinion. Newcastle and Sunderland would be my second choice for qualification of a "twin city" in the UK.

I guess a few criteria for defining a true "twin city" would be useful, and this is what I can think of:

To qualify, I want the following hard criteria:

-A minimum of 500K in the metro, both central components need to be in excess of 250K together, with none of the two central cities below 100K. We want "twin cities", not "twin villages" or "twin towns".
-The smallest of the two central cities needs to be at least three times larger than the largest suburb, otherwise it's more of a conurbation.
-The largest of the two central cities may not be more than twice the population of the smallest, otherwise the two central components aren't equal enough.
-There should also be no regional centres in their own right located between the city centres of both cities.
-No third city of at least regional importance within commuting distance of one of the two urban cores of our twin city candidate, as this makes it a conurbation.

Somewhat "softer" criteria:

-Both components in the "twin city" should be of national importance in case of a binational twin city, or the twin city as a whole is considered to be of national importance in case of a twin city located in the same country.
-No more than 10 kilometres of farm land between the built-up area of the two central components
-The urban core of both components should be within commuting distance from each other; no more than 30 minutes with fast transit (train, light rail, metro) or 60 minutes with slow transit (bus, tram) between the two main urban transit terminals of the main components.
For automotive transit, this can be translated as maximum 30 minutes centre-centre in light to moderate traffic, and maximum 60 minutes when in heavy rush-hour traffic.

-Bonus points if the respective cities are referred to as a combination in official language, extra bonus points if the man on the street does it in everyday language.

And applying these criteria I can come up with the following list:

1) Arnhem-Nijmegen, Netherlands.
2) Leeds-Bradford, Newcastle-Sunderland, UK and Mainz-Wiesbaden, Germany. (although for the latter, Frankfurt might be too close)
3) Gdańsk-Gdynia, Poland (would be first tier if they weren't refered to as Trójmiasto, where in reality they are a twin city) and Leipzig-Halle, Germany (slightly too far from each other)
4) Copenhagen-Malmo. Has the potential of becoming a twin city, but the steep tolls to drive a car across the Oresund makes it in my opinion less so. The trains aren't really cheap either, so it's not attractive for blue-collar workers to live in one city, and work in another, despite the fact that wages in Denmark are much higher. Also, Lund is a bit too important of a city (major academic centre) to comfortably make CPH-MMX quality as a "twin" but this might be offset by the sheer population difference between Lund and the other two, as well as the difference in importance, CPH is a world city, and Malmo one of the three major centres of Sweden, where Lund is primarily an academic centre.

Any additions are welcome :-)

[dunno what to put here]

I think Newcastle-Gateshead would be better, they are located on opposite sides of the river but Newcastle is a city while Gateshead is a town.. they are often referred to as Newcastle-Gateshead.

[Proterra]

Originally Posted by dunno what to put here

I think Newcastle-Gateshead would be better, they are located on opposite sides of the river but Newcastle is a city while Gateshead is a town.. they are often referred to as Newcastle-Gateshead.

The fact that they are often refered to as Newcastle-Gateshead is the reason why Newcastle-Sunderland doesn't qualify for "1st tier" in my list.

Gateshead is small, is economically dependent on Newcastle and in my opinion, much more suburban in character, although with a proper city centre (which a true suburb lacks)
I guess it would be similar to calling Phoenix-Mesa in the US a "twin city" (provided there would not be another 10 "Mesa's", though smaller, around there)

In my opinion, Newcastle-Sunderland is the "true" twin city, and everything else is a combination of old towns and modern suburbs filling the metro.