Artist Joe Sacco has created an immense 24-foot panoramic depiction of the WWI Battle of the Somme (July 1, 1916) spanning the long metro tunnel in Montparnasse station (in the corridor between Metro line 4 and the train station). It was one of the deadliest battles, with 20,000 dead and 40,000 wounded in one day. The artist uses a graphic-novel style with no words to depict the horrors of trench warfare. Worth seeing, even if it means you have to go into the Montparnasse metro labyrinth (through August 31). If you can’t make it, the artist’s book, The Great War also includes it.