I've been in Reykjavík since March 07, and I still don't feel very integrated. I don't think I will ever feel that way, unless I spent at least 5 more years here. This has a lot to do with the people and the language and the culture.
However, my attachment to the city has been growing this summer, since I've been walking to work and back everyday instead of taking the bus. The walk is a bit over 2 miles each way, and there is more than one path that I use. Therefore I feel much more familiar with the town and its streets and its houses. Knowing where the pretty houses are, where I can see more cats on my walk
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, where the moss on the houses is greener, where the traffic is lighter, where the alleyways take me between houses, where the espresso is better and where lunch is cheaper... It all adds up to "knowing" more of the city, and thus belonging in it more.
I guess I belong to an area when I know it by foot. I did not feel like I belonged in South-East PA since I had to drive most everywhere (although I would still walk sometimes from my house to the downtown in the small town I lived in, West Chester). By contrast I felt much more integrated in State College, PA (my college town) since I walked and biked everywhere there. And even in my hometown of Beirut, I feel much closer to the Western part than the Eastern part (though the latter can be prettier) because I never went there much until I was a teenager, since the town was split during my childhood. I guess I would have a hard time in suburbia.