In 1965, Angelos and Niki Goulandris channeled their love for ecology and conservation into this nonprofit museum, which collects, preserves, and displays zoological, botanical, marine, rock, mineral and fossil specimens. The Gaia Environmental Research Center focuses on human impact on our earth, another of the founders’ related concerns. The museum, housed in a converted 19th-century villa, is not huge but it’s packed with interesting things for young people, and an afternoon in Kifissia—a lovely residential neighborhood in northern Athens—provides a welcome break from the buzz of the city center.