Various graphical travel itinerary visualization systems have in recent years been developed to allow making easier references between different events such as flights and hotel bookings on a travel itinerary, thereby addressing a problem with tabular itineraries which list travel events in a chronological order of date and time, and only allow referencing consecutive events. These graphical travel itinerary systems are based on a linear visualization of travel events. Although this linear visualization deals with some of the problems associated with tabular itineraries, it is not the only form of visualization which might be capable of addressing these issues. This paper introduces a new visualization of travel itineraries, called the calendar visualization, which relies on a more familiar concept of calendars to depict the relationships between travel events. This paper also describes an empirical study undertaken to compare the calendar and linear itinerary visualizations.