As part of the ongoing restoration problem on the Acropolis, a team of experts have been surveying the walls of the monument to see if water seepage is causing any damage. It is interesting to note that the surface of the Acropolis that we see today is the result of excavations – originally the ground was higher in many areas.
Kathimerini (English Edition) 
Tuesday March 7, 2006
Acropolis mountain climbing
Archaeologists carrying out conservation work on Greece’s most prized monument have hit on a new extreme sport, one unlikely to feature in visitor tours anytime soon — rappeling down the walls of the Acropolis, the ancient citadel overlooking Athens.
Part of an operation to determine the condition of the walls — which are over 2,300 years old — the stunt teamed conservation experts with veteran mountaineers enlisted to place electrode sensors on the citadel’s southern side, a senior archaeologist said on Sunday.
Maria Ioannidou, the senior archeologist in charge of conservation work on the Acropolis, said the sensor readings would be used to compile a geological scan of the walls and detect any possible damage caused by centuries of soil erosion and water seepage.
“The original surface of the citadel was much higher; what we see today is the result of several excavations,” Ioannidou told AFP. “As a result, there is the possibility of water seeping into the walls. We are just inspecting the wall’s condition at this stage,” she added. (AFP)