the Salton Sea May 29, 1905: A poorly designed irrigation project fails, accidentally creating California's largest lake. A dike gives way, sending Colorado River water pouring into a deep depression in the desert. Today, the Salton Sea (at right) is a major stop for migratory birds, but it is suffering from major pollution issues. Ironically, within two decades of the Salton Sea's birth, another large California lake, Owens Lake, is drained as a result of the growing water needs of Los Angeles.

May 29, 1953: Sir Edmund Hillary and Tenzing Norgay become the first to reach the summit of Mount Everest , the world’s highest peak.

May 29, 1969: Sir Wallace Herbert and his team of Arctic explorers complete a 15-month trek across the Arctic Ice Pack. They arrive in Spitsbergen, northeast of Norway, after departing from Barrow, Alaska, in February of the previous year.

Photo: Deidre Woollard /Flickr

This feature is compiled by Peter Dykstra, an MNN contributor and publisher of Environmental Health News and The Daily Climate .