Hallstatt, Austria, besides being idylic, is a UNESCO World Heritage Site, and is historically fascinating: A Bronze Age cultural center, with a 2,500-year-old salt mine (the world's first); beautiful ice caves; and a Catholic cemetery so small that the dead were regularly disinterred after a time, their skulls painstakingly identified and decorated and stacked in an ossuary.
posted on Aug 28, 2007 - View this thread

Wieliczka Salt Mine in Poland has been in operation for 800-odd years. Needless to say, this has given the miners plenty of time to carve some pretty amazing things. More photos here and here. Videos here and here. Virtual tour here. Wikipedia.
posted on Aug 16, 2007 - View this thread