Abstract: Researches on super-topic communities often focus on the shared interests, but the communicative value of city super-topic community is ignored. Taking Chongqing super-topic community as the subject, this study makes a text content analysis of the 400 selected microblog samples, and explores the potential of communicating of city microblog super-topic communities, and the triple dimensions of urban communication reflected by micro-blog super-topic mechanism. The analysis shows that as an information network, city super-topic community provides a platform for urban residents to seek social support and communication, with city watchdogs and observers getting involved;as a geographical network, city super-topic community serves to draw a three dimensional outline of the districts and counties;as a network of meaning, city super-topic community brings the city into a community, offering the city residents shared identity of being local. As city in a virtual community, city super-topic community has a strong urban attribute, with the connotation of "multiple integration, space-time balance, virtual and reality inter-embedding, and internal and external connection" of a communicable city.

Key words: communicable city, city super-topic community, urban communication, city identity, virtual community