It is narrated from Hazrat Abu Huraira (may Allah be pleased with him) that the Holy Prophet (peace and blessings be upon him) visited his mother's grave and wept, and those with him also began to weep. The Holy Prophet (peace and blessings be upon him) said: I asked my Lord for permission to seek forgiveness for my mother, but I was not granted permission. I then asked for permission to visit her grave, and that was granted. Therefore, visit the graveyards, for they remind one of death.