There was nothing used by Daesh* (ISIS) that the Syrian and Russian ordnance disposal specialists were unfamiliar with. But the breadth and detail of the wiring and explosives Daesh placed hidden among the ruins were found to be very sophisticated.
The Daesh plan which was also apparently referenced in a document later recovered from the Museum was dubbed “Erase.” (“Mahaqa” in Arabic). Daesh planned to “Erase” the whole area of our ancient ruins and Daesh hoped to kill at least 1000 Syrian troops who they assumed would be among the ruins when they were detonated.
The dangerous work of clearing the unexploded ordnance was performed by many to date unsung heroes; among them are 100 Syrian and 200 Russian unexploded ordnance specialists and 11 Russian explosive detecting dogs.
Some robots were all deployed as part of the massive around clock bomb clearing operation.
At the end of the intense 30 days of heroic work, which claimed the lives of two soldiers and wounded others, no fewer than 4000 booby-trap bombs were defused and removed from among our cultural heritage ruins at ancient Palmyra.
Experts at Palmyra have recently formed three units specializing in engineering, archeological evaluations and restoration of damage artifacts. As noted above, it is widely believed here that 95% of damage caused by Daesh can and will be restored.
Even a higher percentage can be restored some archeologists working here estimate. And 95% of all the ruins were untouched.
Source: How 100 Syrians, 200 Russians and 11 Dogs Out-Witted ISIS and Saved Palmyra
*Why Isis hates being called Daesh