The Quba Mosque (Arabic: مسجد قباء, Masjid Qubā’), in the outlying environs of Medina in Saudi Arabia, is the oldest mosque in the world. Its first stones were positioned by the Islamic prophet Muhammad as soon as he arrived on his emigration from the city of Mecca to Medina and the mosque was completed by his companions. Muhammad spent 14 days in this mosque during the Hijra praying qasr (a short prayer) while waiting for Ali to arrive in Medina after the latter stayed behind in Mecca to carry out a couple of tasks entrusted to him by the Prophet.
According to Islamic tradition, offering two rakaʿāt of nafl prayers in the Quba Mosque is equal to performing one Umrah.
Muhammad used to go there, riding or on foot, every Saturday and offer a two rak’ah prayer. He advised others to do the same, saying, “Whoever makes ablutions at home and then goes and prays in the Mosque of Quba, he will have a reward like that of an ‘Umrah.” This hadith is reported by Ahmad ibn Hanbal, Al-Nasa’i, Ibn Majah and Hakim al-Nishaburi.