Bam: Said to be the largest mud-brick structure in the world
The historic Iranian city of Bam - devastated by a massive earthquake - is one of the country's most popular tourist spots and is best known for its historic, 2000-year-old citadel.
Built out of mud bricks, clay straw and the trunks of palm trees, it is said to have been the largest structure of its kind in the world.
But a large part of the historic citadel has been destroyed.
Most of the monuments visited every year by thousands of tourists date back to the 16th and 17th Centuries, the heyday of the Safavid dynasty.
But they too have been badly damaged by the earthquake that struck the south eastern city on Friday 26 December.
"The city of Bam must be built from scratch," said its governor Ali Shafiee.
During the Safavid period (1501 -1736), Bam occupied six square kilometres and was surrounded by a rampart with 38 towers. It had a population of between 9,000 and 13,000.
Bam flourished as a site of pilgrimage and as a commercial and trading centre on the famous Silk Road which brought the treasures of the ancient Far East into what was Persia, and on to the Mediterranean and the fashionable capitals of Europe.
Following an Afghan invasion in 1722, Bam declined in importance.
The city was used as an army barracks until 1932 and then abandoned.
In 1953, the Iranian authorities began to dedicate teams of architects and historians to restoring the old quarter, attracting thousands of visitors.
Now, it appears, much of that heritage may have been lost forever.