What is the ruling on building graves with bricks, marble, and the like?

Building on graves is not permissible at all; it is forbidden because the Prophet, peace and blessings be upon him, prohibited it and leveled every raised grave. Building on graves leads to great evils, such as the ignorant believing in them and seeking the fulfillment of needs from them, undertaking journeys to them, and other practices that the people of Jahiliyyah (pre-Islamic ignorance) used to do with idols. Moreover, building on graves leads to taking them as places of worship, and the Prophet, peace and blessings be upon him, cursed those who do so. As for those who consider it disliked (makrooh) rather than forbidden (haram), they stipulate that the intention behind building should not be ostentation or boasting, and that it should not be in a public cemetery due to the space it occupies.