There are many theories and concepts aiming at describing and measuring the modern cities in the 21 st century: digital city, smart city, creative city, knowledge city or global city-each of them with different infrastructure and diverse components. In the present case we combine all these aspects, quantify and measure them under the concept of the informational city. We are using methods of the information science approach on urban studies, including the ethnographic field study, grounded

more »

... y method and further research-based proceedings. While looking for informational cities we evaluate as case studies the advancement of four Japanese cities in regard to various aspects and conclude which of them mostly conforms to the expectations of the 21 st century city.