the second holiest place for muslims is the masjid al-nabawi in medina, which is where the prophet muhammad is buried under the green dome. caliphs umar and abu bakr are also said to be buried in the masjid al-nabawi. the al-aqsa mosque in jerusalem is a sacred place in sunni traditions as the site from which muhammad ascended to heaven in the isra and mi'raj and was also the first qibla. mount sinai also holds significance in islam. among shias, the imam ali mosque and imam husayn shrine also hold high significance.