Is there a prescribed time period to keep cemeteries? I heard that after 100 years a cemetery should be switched to a different use (e.g. agriculture, housing,…). Is this true?

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger. We ask Allaah to exalt his mention as well as that of his family and all his companions.

There is no evidence that, as the questioner mentioned, after 100 years graveyards should be transformed into something else. Rather, the scholars are of the view that it is not permissible to dig up graveyards unless we are certain that they are free from any buried body parts.

One Maaliki scholar said: 'It is not permissible to dig the graves as long as a dead body is there, but if one is sure that there are no remains of the dead, then it is permissible to dig it in order to bury other people in it.'

So if there are tombs in a graveyard where there are remainders of the dead and people still bury their dead in them, then it is not acceptable to dig it or transform it into agricultural land, or build estates, or anything else. However, if the graveyard is extinct, meaning a graveyard where dead people were buried but there are no remains of them, then the Hanafi and Hanbali schools are of the view that it is permissible to transform it into agricultural fields, or build estates while the Maaliki school prohibited it. Nevertheless, if the graveyard is an endowment, then it is not permissible to use it for anything other than burials.

To conclude, there is no specific time for benefiting from a graveyard or transforming it into something else, but the decision depends upon whether there remains some parts of the buried. If there are parts of the dead, it is not permissible to dig there, but if it is extinct, it is permissible to use it for other purposes than burials if such a graveyard is not designated to be used only for burials.

Allaah knows best.