A Release Train Engineer (RTE) uses an Iteration and Program Increment (PI) Calendar to visualize the Agile Release Train's cadence and synchronization. This calendar is a critical tool in SAFe for planning and tracking the events and milestones of a PI. It helps in aligning the team with the ART's schedule, ensuring that all teams are working in sync and that key events such as PI Planning, Iterations, and Inspect and Adapt sessions are conducted at regular intervals. The calendar serves as a visual aid to manage the flow of value through the ART by providing a clear view of the PI timebox, which typically includes four development Iterations followed by one Innovation and Planning (IP) Iteration1. By using this calendar, the RTE can facilitate a smooth and coordinated execution of the PI, which is essential for achieving the goals set out in the PI Objectives23.