Advanced tourist information systems should offer more than relatively static information about sights and places. Instead, semantically-rich information about sights (e.g., groups of sights with same characteristics) should be delivered to the mobile users. Furthermore, tourists should not be overwhelmed by a stream of superfluous data that are unrelated to their interest, location, and knowledge of a place. Personalization of the information delivery to each traveler, together with his or her travel history, is therefore crucial. This paper presents the major design issues of the personalized Tourist Information Provider TIP. TIP is a combination of an event-based system (EBS) and a location-based service (LBS) applied to a mobile environment. We discuss the lessons learned from developing its kernel using a semantic network of sight-related information and considering the travelers' interest and travel route, with emphasis on modeling decisions and their impact on the final system.