At the location where this mosque now stands, the Prophet ﷺ prayed the Maghrib and Isha prayers on the eve of Eid al-Adha during his Farewell  Pilgrimage. He stayed in this location until dawn, and then prayed Fajr before facing the Qibla and engaging in remembrance and supplication. As the morning light appeared, he headed in the direction of Mina.
At the beginning of the third century after Hijrah, a mosque (masjid) was built at the site where the Prophet ﷺ prayed. It was named 'Masjid Al-Mash'ar Al-Haram' in accordance with the Quranic verse: 'When you depart from 'Arafat, remember Allah at Al-Mash'ar al-Haram.' The space surrounding the mosque was enclosed by a wall, and the mosque itself underwent various renovations over the centuries until the prosperous Saudi era, standing witness to the important events that took place during the Farewell Pilgrimage and serving as a place of worship and remembrance.