Sayyiduna Ibn Abbas (may Allah be pleased with them both) narrated: When Ibrahim (peace be upon him) was commanded to proclaim Hajj among the people, the settlements were raised for him and the mountains were lowered, so he said: O people! Accept the call of your Lord, so they accepted it.
Hadith Referenceمسند اسحاق بن راهويه / كتاب المناسك / 388