SOUTH BANK. Occupying the Bethlehem Royal Hospital building (known more familiarly as "Bedlam" in past days), this museum traces 20th-century wars. Its graphic, compelling exhibits illustrate the impact of conflict on bystanders, participants, and innocents swept up in the waves of horror. Interactive exhibits place folks in WWI trenches and in Blitz-era bombings, and the Holocaust exhibit frequently elicits a visceral reaction from visitors. Artifacts and multi-media displays communicate the devastating impact of war, which can be overwhelming for children. However, the museum now offers a special exhibit that looks at war from a child's perspective and gives them a voice. TUBE: Lambeth North or Waterloo