Arabian Peninsula (including the island-state of Bahrain) Building Image Location Country First built Denomination Notes Al-Masjid al-Nabawi Medina Saudi Arabia 622 Second holiest site in Islam (after Al-Haram Mosque) and Muhammad's mosque, which houses his tomb in what was initially his and his wife Aisha's house. Largely rebuilt and greatly enlarged in the late 20th century, whilst retaining at its heart the earlier construction of the Ottomans, and landmark green dome atop the prophet's mausoleum.