Collaborative IT networks are suitable to model and represent the interconnected maritime ports that in nowadays globalized world are poised for tremendous growth. Actually, there are already such strongly connected collaborative networks mainly serving national purposes. Although, there are almost no collaborative networks for maritime port B2B platforms for cross border services. Here, we present a pilot collaborative network that was built to serve in Adriatic Sea among three heterogeneous and autonomous maritime port community systems (PCS). Their integration was based on a cross border platform that dealt with several challenges and met all the key requirements set by the stakeholders. In this paper we present the design details of this innovative platform, the experimental results of the prototype and the potential for wide use.