This disaster is entering its fourth day.
70% off all buildings in Bam were razed to the ground
The enormity of the challenge that lies ahead is daunting.
The scale and suddenness of the devastation means thousands of survivors have lost not only their homes, but everything else they had.
They are destitute, living on the streets because their homes are destroyed and because they are afraid aftershocks could bring down the few buildings they could shelter in.
While some have been given tents, others have spent the long cold nights simply wrapped in blankets and out in the open, or huddling around fires to keep warm.
Many buildings were made of mud brick, which disintegrates into tonnes of rubble and debris, leaving little hope of survival for those buried underneath.
The digging will go on though, for many people are known to be still entombed in the wreckage of the homes where they were sleeping when the earthquake struck.
Survivors can be seen everywhere weeping in anguish.
They know there is virtually no chance now that loved ones could still be alive under the heaps of rubble.
There is a shortage of digging equipment and shifting the rubble by hand is tough work
International rescue workers who flew in here in their hundreds to help save people are now packing up and preparing to leave.
Rescue workers are preparing to leave Iran
They have come to the grim conclusion that there is nothing more they can do.
They would have preferred to stay and save lives but now the effort to tackle this crisis is moving into a new phase.
A start has been made to the immediate task of providing emergency shelter and food to the survivors.
But beyond that lies the monumental challenge of rebuilding this historic city and the lives of those who survived this disaster.