What was the 1st calendar made of (material)?

The first calendars were primarily made from natural materials such as wood, stone, and bone. Ancient cultures often marked time by carving or etching markings onto these surfaces to track lunar cycles and seasonal changes. For example, the ancient Egyptians used papyrus, while the Mayans created complex calendars using bark paper. These early calendars reflected the materials readily available to the civilizations that created them.