Beijing holds eight of the universities we cover, and they are not a random sample. Tsinghua and Peking anchor the technical and comprehensive end; Beihang covers aerospace and software; Beijing Institute of Technology covers automation and vehicle engineering; Normal University is the reference point for education, psychology and teaching Chinese as a foreign language; Language and Culture University exists specifically to teach Chinese to foreigners and has the deepest curriculum for it; Capital Medical University and Beijing University of Chinese Medicine cover western and traditional medicine respectively.
That density is the real argument for Beijing. If your target is computer science, engineering, economics, international relations or Chinese language teaching, there is a top-five programme in this city for every one of those. You do not have to compromise on the subject to get the location, or the other way round.