Dublin's story is of feast and famine - from its 18th-century Golden Age to its 20th-century struggles for independence to its boomtime today. We explore the town's foreboding castle, patriotic jail, and Trinity College with its Book of Kells-a bright light in the Dark Ages. At night we party in Temple Bar, awash with Celtic music and frothy pints of Guinness. We side-trip to the prehistoric necropolis of Newgrange and the medieval monastery at Glendalough, tucked in the scenic Wicklow Mountains.