Twain's boyhood home in Hannibal, pictured circa 1955, is now a museum. Three Lions/Getty Images hide caption

itoggle caption Three Lions/Getty Images

After John F. Herring by Ken Perenyi, circa 1989. Courtesy of Pegasus Books hide caption

itoggle caption Courtesy of Pegasus Books

Edward Hopper's wife, Josephine N. Hopper, served as his model for 1952's Morning Sun. Columbus Museum of Art/Howald Fund hide caption

itoggle caption Columbus Museum of Art/Howald Fund

De Waal's 2012 work all and more is on display in the Dining Room. It is made up of 23 porcelain dishes: 22 in white and cream glazes and one gilded dish, contained in a clear glass vitrine. Paul Barker/The National Trust, Waddesdon Manor hide caption

itoggle caption Paul Barker/The National Trust, Waddesdon Manor

Andy Cao and Xavier Perrot's Red Bowl installation in Beauvais, France, recalls the way lepers once bathed in animal blood in an effort to cure themselves and avoid being ostracized to the one-time leprosarium where the installation is located. Courtesy of Cao | Perrot Studio hide caption

itoggle caption Courtesy of Cao | Perrot Studio

Lucy Hessel, depicted above at the seaside in 1940, was Vuillard's friend, muse and lover for more than 40 years. She was also the wife of art collector and Vuillard supporter Jos Hessel. Vuillard was with Hessel when he died in June 1940. Hammer Museum, Los Angeles hide caption

itoggle caption Hammer Museum, Los Angeles

Claude Monet observes his Giverny, France, garden from its Japanese footbridge in this 1922 colorized. Courtesy of the New York Botanical Garden hide caption

itoggle caption Courtesy of the New York Botanical Garden

Antonio Manfredi, director of the Museum of Contemporary Art in Casoria, Italy, burns an artwork by French artist Severine Bourguignon. Manfredi is burning the museum's works to protest deep cuts to the arts. Roberta Basile/AFP/Getty Images hide caption

itoggle caption Roberta Basile/AFP/Getty Images

After years of bitter controversy, the Barnes Foundation opens the doors of its new location in downtown Philadelphia on Saturday. Since 1922, the collection has been housed in the Philadelphia suburbs, where critics say the collection's owner would have wanted it to stay. Tom Crane/The Barnes Foundation Philadelphia hide caption

itoggle caption Tom Crane/The Barnes Foundation Philadelphia

Students and seniors discussed Claude Monet's Sunset at Pourville during a recent visit to the Kreeger Museum in Washington, D.C. The Kreeger Museum hide caption

itoggle caption The Kreeger Museum