Musannaf Ibn Abi Shaybah 35879 — What one returning from a journey

It is narrated from Sayyiduna Ibn Umar (may Allah be pleased with them both) that when returning from an army, an expedition, Hajj or Umrah, whenever the Prophet (peace and blessings be upon him) came upon a mountain pass or level ground, he would say the takbir three times and then recite this du'a: 'La ilaha illa Allah wahdahu, sadaqa Allahu wa'dahu, a'ibuna ta'ibuna abiduna, li-rabbina hamidun' (There is no god but Allah alone; Allah has fulfilled His promise; we are returning, repenting, worshipping and praising our Lord).