Determining the timing of the initial continental collision is a fundamental step in accurately reconstructing the paleogeodynamic evolution of orogenic belts. This process necessitates a comprehensive integration of evidence gathered through various analytical techniques, both in the field and in the laboratory, to achieve a conclusive understanding. We here use comprehensive methods, including sandstone petrography, U-Pb dating, trace element and Hf isotopic compositions of the detrital zircon, in the Haji Abad (eastern Zagros Orogen) and the Shamil areas (west of the Minab-Zendan Fault) to constrain the timing of the initial collision between Arabia and Eurasia. Zircon U-Pb dating in the Haji Abad area reveals that detritus predominantly originates from the Arabia Pan-African basement (∼640 - 539 Ma, Ɛ