ISRAEL: Apparently even 800 years ago, Crusader forces were aware of the concept of always leaving yourself a way out of a sticky situation. Conservation and restoration work in the old city of Tiberias exposed a secret escape tunnel that once connected the 12th-century Crusader citadel directly with the harbor on the Sea of Galilee. The surviving 21-foot section may have been used during times of turmoil, especially when the fortress was besieged by the Muslim general Saladin in 1187. —Jason Urbanus