Dalian or Qingdao would be a good choice, both matching your criteria and I can really recommend them.

Actually, each city has its own dialects and accent even in north china where most people can speak mandarin(putonghua).

I recommend Tianjin, Qingdao and Dalian
Actually, in Shanghai, people in university speak perfect mandarin

in Shanghai or zhejiang,people in university speak perefect mandarin.

te recomiendo shanghai!
vivo en shanghai!jaja

Why not come to Shanghai? It's more easier for your english-speaking people come to Shanghai to start to learn Chinese. Everyone know English more or less.

Tianjin dialect is closed to standard Mandarin,
but its tones are different from pure Mandarin,
especially the first tone (阴平/一声) always sounds strange,
and there're a lot of local words which might be difficult to understand for foreign Mandarin learners.
But Tianjin is still a good place to settle down.

BTW, Tianjin, along with Shanghai, is a coastal city,
& so are Qingdao & Dalian, but unluckily Heibei isn't.

http://www.bfsu.edu.cn/publish/default_en.aspx (English Version)

北京外国语大学（Beijing Foreign Studies University）

Beijing is the best choice. Because Beijing dialect is almost mandarin. There is not so far from Beijing to Tianjin, you could get there by train only half an hour. Actually I think the coastal cities which close to Beijing are not as good as you image. The sea water is not very clean.
And if you want to choose a place which you have listed above, i advise you don't choose Shanghai and Tianjin. I think よしや had said so clear.

do google search,it is the easiest way learning about chinese,chinese people,chinese culture,...,you are losing your time in this frame!

I can help you.

totally I agree with the city Tianjin, I was graduated there, but also I think that's a city comply with your requirement! There are very famous universities there, it's coastal and it's near by Beijing :)

Just one thing you should pay attention to, don't learn the local patois :)

thought it over again, I'd have to say that for your situation and if you need to hear mandarin, Beijing would be a great choice, and might be the only choice suitable :)

You want to speak standard chinese mandarin? I suggest Harbin. They speak very standard and their local dialect (dong bei hua) is not far off from mandarin. Ask anybody from harbin and they will tell you how proud they are of their "standard chinese speaking" furthermore it is cheaper to learn in harbin then in other cities. (rent, food, tuition etc). many korean and japanese people go to harbin to study for the HSK. there are two main universities (哈工大）(黑龙江大学）both have good chinese teaching programs. I go to a private chinese school in harbin as I'm also an english teacher and don't have time for regular school. I have three different chinese classes three times a week. they are all one on one and my teachers (three different teachers) can't speak english which forces me to use mandarin. furthermore, in this city you need mandarin and will speak it everyday. from the doctor's office to buying food.

The only drawback to harbin is its weather. It gets pretty cold here during the winter. But because I'm a Canadian I use to it.

if interested in harbin leave me a message I would be glad to help you out. Good Luck.

Tianjing isthe best city for you .It is close to Beijing and sea.Besides,It is a city with universities, safe, beautiful, clean and modern.