German tourists up the wall at Colosseum

A pair of German tourists recently slipped through night-time security at Rome's 2000-year-old Colosseum and scaled the walls. They also filmed themselves and posted the video on YouTube.

The incident has raised new criticism of how Rome secures its treasures and archaeological sites. In an era where terrorist threats are all around, some Romans are fearful of what may come next. 

Other recent incidents have included wading in the Trevi Fountain. The waders have been fined, but so far the climbers have not been identified.