Why did the Romans bury people in the catacombs?
The Romans begun to build catacombs in the 2nd century AD due to
overcrowding which created a shortage of land for burial. It is
widely believed that the Christians created catacombs to bury their
dead secretly and to hide from the persecutions. Historians
disagree because their sites were known and they because they could
not be kept secret due to the smell form the dead bodies reaching
the surface. Moreover, not all catacombs were Christian and some of
them were mixed (both Christians and pagans were buried in these).
Lack of land and the nature of the volcanic rock beneath Rome are
more satisfactory explanations. This rock is easy for tunnelling.
It soft when it is exposed to air and then harden, making the
catacombs safe.