The earthquake that devastated this medieval town would likely have caused only limited damage in Japan and other affluent countries in quake-prone regions, but a variety of factors conspire to make Italy particularly vulnerable, experts said.

While L'Aquila sits about 1 km from the epicenter of Monday's quake in the Apennine region of Abruzzo, geologists and civil engineers attributed most of the blame for damage on inadequate buildings.

"The collapses that occurred in Abruzzo involved houses that weren't built to withstand a quake that wasn't particularly violent," said Enzo Boschi, president of the National Institute of Geophysics and Vulcanology. Italian authorities put the quake's preliminary magnitude at 5.8, while the US Geological Survey recorded it as 6.3.