Newly energized Prague, slinky with sumptuous Art Nouveau facades, is perpetually playing Mozart and Vivaldi. Eastern Europe's top destination has Europe's best beer, biggest castle, liveliest pedestrian bridge, and most evocative Jewish Quarter. From Prague, we side-trip to Kutna Hora, once a silver-mining boomtown, to descend into its medieval mine and ponder its eerie chapel, decorated centuries ago with 40,000 bones.