From the Guardian: Turkmenistan Ruins at Risk of Crumbling.
MERV, Turkmenistan (AP) - Genghis Khan's hordes couldn't wipe the great city at Merv from the earth when they killed thousands here in their bloody wave of conquest. Centuries later, though, modern man's meddling with Mother Nature threatens to obliterate the remains of the metropolis.
Merv enjoyed a golden age during the 11th and 12th centuries, when the Sultan Kala fortress was the eastern capital of the Turkish Seljuk Empire and one of the world's biggest cities. Legend says the blue dome of the Sultan Sanjar mausoleum was visible a day's journey away. Even when Mongolian warriors led by Genghis Khan's son sacked the city in 1221, killing what a 13th century historian claimed were 1.3 million people, the city still stood.
Today, the mausoleum is still Merv's crowning landmark, but the dome's blue tiles disappeared long ago. Well-intentioned Soviet efforts in the 1980s to preserve the structure by capping the dome with concrete did more harm than good, trapping water inside and weighing it down.
Now Merv is a Unesco World Heritage Site, and
...preservationists funded by UNESCO have dug pits across Merv, looking for the right earth to build new bricks to help shore up the buildings' walls. Bendakir said residents had forgotten traditional methods for making high-quality mud bricks, so the preservationists experiment with different proportions of mud and water, sometimes adding straw or lime. [continue]
(Story spotted at Phluzein.)
Related links:
Photos of Merv Fantastic thumbnail shots. Registration required if you want to see full size photos.
Merv, Turkmenistan, excavations from the British Museum's Department of Ancient Near East
The International Merv Project, Turkmenistan
Merv, Turkmenistan - Galen R Frysinger's travel photos