This paper presents preliminary results of utilization of Event-B for domain modeling. The development of new urban transport systems, based on autonomous vehicles, strongly requires the formal description of land transportation domain. Certification, safety, or security, for instance, crucially depend upon formal assessment that systems meet the required properties and constraints of the domain. Though Event-B has not been designed for domain modeling, yet, it was discovered that its notions of events and non determinism are well suited to formalize a domain with many autonomous agents. Refinements and systematically constructed proof obligations work well in this context, but we also need other operations in the modeling process, such as, "abstraction leaps" which have been introduced as a part of domain specification.