Multiagent-based simulations are regarded as an useful technology for analyzing complex social systems and have been applied to various problems. Tackling the problems of a city involves various levels of abstraction and various target domains. Different types of human behaviors are studied separately by specialists in their respective domains. We believe that we need to integrate simulators that offer different levels of abstraction and cover various target domains. This paper introduces the architecture of a simulator integration platform and demonstrates the capability of the platform in that domains of city traffic and city electricity.