Leaving aside the more localized communities referenced above, here's Merriam-Webster's Dictionary on the definition of "community":
1 : a unified body of individuals: as a : state, commonwealth b : the people with common interests living in a particular area; broadly : the area itself <the problems of a large community> c : an interacting population of various kinds of individuals (as species) in a common location d : a group of people with a common characteristic or interest living together within a larger society <a community of retired persons> e : a group linked by a common policy f : a body of persons or nations having a common history or common social, economic, and political interests <the international community> g : a body of persons of common and especially professional interests scattered through a larger society <the academic community>
If you look at the latter definitions, you'll note that physical proximity isn't necessary when discussing a community. This also matches the way it's used more colloquially today as virtual "communities" are enabled by widely available access to internet-driven forms of communication.
Think about it... if there's a group of people who share your values, experiences and interests, and whom you interact with on a regular basis... how is that not a community?