Don’t overlook McGill in Montreal. Berkeley is a lively city in its own right, but it’s right across the bridge (with easy public transportation) from San Francisco.
@fuzzzzzzster yeah, Northwestern as well - a little further away from downtown than UChicago, but still Chicago. Nice campus/location. Excellent university.
By the way, unless you’re a stellar student - and even if you are - you shouldn’t only be looking at the most selective colleges (Northwestern, Columbia, Chicago, etc.) because your chances of getting in aren’t high (for anyone). Be sure to have some backups as well depending on your scores/etc.
So what? You think the rest of us fell off the turnip truck? Why don’t you just state EXPLICITLY what qualities you seek in a school and stop assuming that living in a “big international city” somehow implicitly defines what you want.
@insanedreamer I know I know, I’m not assuming anything…just shortlisting I guess as I may not actually be able to visit before I apply 
@GMTplus7 Nope don’t think any of you ‘fell of the turnip truck’ - I can’t explicitly state what qualities I’m seeking because I myself don’t know what they are…if that makes any sense. The reason I asked a broad question is to see what came to the minds of other users when they read what I implied. Everyone else seems to have gotten the idea
@fuzzzzzzster Before you get too deep in this what is your GPA and ACT/SAT. Any accomplishments or talents a college might find interesting?
OP - where do you live? I am assuming a large Asian city such as Mumbai or Karachi?
My H and I both chose quintessential college towns for our undergraduate experience which were smaller than where we lived. My D went somewhere larger than her hometown, S ended up selecting a college in a town smaller than his hometown. Between studies, a few extracurricular activities and working part time, they didn’t have lots of free time.
Will you have access to a car? Some colleges are situated where having access to a car is almost a necessity. My kids didn’t have cars, but used ZipCar on occasion.
Size of school, climate, ease of travel, geographic location, and size of the city the school is located in are all factors. My D doesn’t care for cold weather but ended up selecting a school with lots of snow because it was a fabulous school.
My H and I recently moved from a small city to a huge one. There are things about each location to be appreciated.
OP - one thing that you want to consider. It will make a huge difference to your quality of life if you can find a school no more than 2 hours from an international airport. Travelling domestically by air in the US is a nightmare particularly if you have just transferred from a 10+ hour international flight. This is one reason why my kids have taken Vanderbilt, WUSTL and CMU etc off of their lists.
@londondad yes, I am now beginning to come to that realisation!
Therefore, your best options are Boston, New York, Washington, Durham NC (if coming from Europe), Miami, Chicago, Houston, LA and SF.
As stated somewhere above, LA is a different kind of “big city” than Boston, NYC, Chicago, etc. It’s plenty big, but there isn’t much “city” to it (sort of).
Here is another similar city rank (I apologize for the formatting, but cut and paste did not work very well and I ran out of time - a link to the source document is included).
To provide some context:
London is the top city in Europe.
Singapore and Hong Kong are the top two cities in Asia Pacific
Dubai is the top city in the Middle East
London, Singapore and Hong Kong are among the top cities in the world, and therefore tough to match.
Dubai is ranked 40th in the world, so that is a little easier to match. There are about 12 cities in North America
(three of which are in Canada), that could be considered. Availability of international flights is one attribute of an “international city” hence the correlation between this list and the list of @londondad.  Don’t get too wrapped up with the exact rank as it will vary somewhat based on how you would weight the different criteria.
For the list of schools I provided in my last post, I used a filter of US cities in the top 20 globally with a location less than 10 miles from the downtown and a less than 20% acceptance rate. If you relax any one of these three dimensions (or include Canada) then more schools will make the list.
Category weight 30.0% 10.0% 10.0% 15.0% 5.0% 15.0% 5.0% 10.0%
 * 1 New York       71.4   54.0   92.0  100.0   85.8 95.0 76.5 66.7 35.7
**2 London          70.4   41.9   90.2   100.0   83.8 92.5 75.6 75.0 65.1
*3 Singapore      70.0   46.0  100.0  100.0   87.8 77.5 69.8 87.5 43.2
****4 Hong Kong     69.3   43.8  100.0  100.0   85.3 79.2 82.4 66.7 37.7
4 Paris               69.3   43.6   93.8    83.3   72.7 90.0 80.1 91.7 64.8
6 Tokyo              68.0   50.5  100.0  100.0 76.3 84.2 64.1 62.5 44.4
7 Zurich              66.8   30.1   98.2   100.0 96.0 97.5 77.9 87.5 26.1
* 8 Washington     66.1   43.4   93.8    83.3 85.8 85.0 77.6 66.7 32.7
*9 Chicago           65.9   40.6   90.2   100.0 85.8 92.5 76.7 70.8 22.1
*10 Boston            64.5   37.9   94.6    83.3 85.8 80.0 77.3 83.3 27.2
   11 Frankfurt         64.1   35.0   98.2   100.0 76.2 92.5 70.5 100.0 21.0 
  *12 Toronto           63.9   32.3   88.4   100.0 87.1 90.0 75.6 75.0 26.8 
   13 Geneva           63.3   29.3   98.2   83.3 96.0 85.0 78.9 87.5 15.2 
  *13 San Francisco 63.3   41.5   89.3   83.3 85.8 85.0 77.6 66.7 15.3 
    15 Sydney            63.1   31.3   98.2   83.3 94.8 95.0 68.7 75.0 25.5 
    16 Melbourne       62.7   31.1  100.0   83.3 94.7 87.5 68.9 83.3 18.9 
    17 Amsterdam      62.4   33.8  100.0   83.3 77.4 87.5 71.9 70.8 36.3 
   *18 Vancouver       61.8   29.9  100.0   83.3 87.1 87.5 75.7 83.3 15.3 
   *19 Los Angeles    61.5   45.7   88.4   50.0 85.8 95.0 76.9 54.2 20.5 
     20 Seoul               60.5   41.1   88.4   83.3 73.1 84.2 61.7 70.8 30.6 
     20 Stockholm       60.5   37.9  100.0   50.0 84.2 85.0 73.2 83.3 21.2 
   *22 Montréal 60.3 30.7 89.3 66.7 87.1 87.5 75.2 100.0 17.5 
    23 Copenhagen 59.9 32.3 98.2 66.7 75.3 82.5 80.2 75.0 24.8 
   *23 Houston 59.9 45.6 82.1 50.0 85.8 82.5 77.3 70.8 8.4 
   *25 Dallas 59.8 43.4 85.7 50.0 85.8 82.5 77.0 79.2 7.0 
    25 Vienna 59.8 36.4 98.2 50.0 74.7 90.0 71.3 87.5 33.3 
    27 Dublin 59.5 31.2 90.2 83.3 67.0 90.0 82.8 75.0 20.9 
    28 Madrid 59.4 32.7 94.6 66.7 69.2 92.5 72.2 87.5 32.3
   *29 Seattle 59.3 42.0 90.2 50.0 85.8 82.5 77.7 62.5 9.2 
   *30 Philadelphia 58.5 38.0 88.4 50.0 85.8 82.5 76.8 70.8 11.7 
   *31 Atlanta 58.2 36.6 84.8 50.0 85.8 80.0 77.3 83.3 11.0 
    31 Berlin 58.2 32.1 93.8 50.0 76.2 92.5 70.3 91.7 30.3 
    33 Oslo 57.2 33.9 98.2 50.0 74.6 75.0 78.1 83.3 13.9 
    34 Brussels 57.1 36.0 92.0 50.0 80.6 80.0 66.6 70.8 24.7 
    35 Hamburg 56.8 35.7 100.0 50.0 76.2 80.0 70.8 83.3 8.8 
    36 Auckland 56.7 28.8 90.2 50.0 95.9 75.0 76.4 75.0 6.5 
    37 Birmingham 56.6 32.0 88.4 50.0 83.8 70.0 74.8 100.0 9.2 
    37 Taipei 56.6 41.9 90.2 50.0 77.5 61.7 66.1 58.3 24.8 
    39 Beijing 56.0 49.8 77.7 83.3 37.6 53.3 64.1 58.3 41.5 
*****40 Dubai 55.9 37.0 82.1 83.3 72.7 49.2 69.1 50.0 20.0 =
   41 Abu Dhabi 55.8 42.5 85.7 66.7 72.7 36.7 71.2 75.0 5.9 =
   41 Barcelona 55.8 33.4 98.2 33.3 69.2 92.5 71.6 70.8 33.8 =
  *43 Miami 55.2 31.5 86.6 50.0 85.8 90.0 76.5 45.8 9.3 
http://www.economistinsights.com/sites/default/files/downloads/Hot%20Spots.pdf
@Mastadon very, very helpful. Thank you so much
Can you clarify? You say you are an “expat”, but are not a US citizen. So you are not a US expat. Perhaps you are originally from another country but currently live in a large international city in a third country? Have you ever been to the US?
Durham, NC is in no way a big city - so strike it.
Philadelphia has a intl airport and you can take PT easily to Newark if you find cheaper/direct flights from there.
As someone mentioned some of large cities listed are not built on the European model of a city - they are basically huge commercial districts surrounded by suburbs.
I agree with scratching Durham if you want anything close like HK or London. The only cities in the US that are close to that style are the older US cities (NYC, Boston, Philly, DC, Chicago, SF).
If you mean "with lots of things to do for young people and walkable " then you want a college town.
If you want a city with an international airport there are many but they may not resemble what you call a city,  depending where you live and are used to.