The Prophet's Mosque (Arabic: ٱلْمَسْجِد ٱلنَّبَوِي, romanized: al-Masjid an-Nabawī, lit. 'Mosque of the Prophet'), is the second mosque built by the Islamic prophet Muhammad in Medina, after that of Quba, as well as the second largest mosque and holiest site in Islam, after the Masjid al-Haram in Mecca, in the Saudi region of the Hejaz.[2] The mosque is located at the heart of Medina, and is a major site of pilgrimage that falls under the purview of the Custodian of the Two Holy Mosques. Muhammad himself was involved in the construction of the mosque. At the time, the mosque's land belonged to two young orphans, Sahl and Suhayl, and when they learned that Muhammad wished to acquire their land to erect a mosque, they went to Muhammad and offered the land to him as a gift; Muhammad insisted on paying a price for the land because they were orphaned children. The price agreed upon was paid by Abu Ayyub al-Ansari, who thus became the endower or donor (Arabic: وَاقِف, romanized: wāqif) of the mosque, on behalf or in favor of Muhammad.[3] al-Ansari also accommodated Muhammad upon his arrival at Medina in 622.