Three Gorges DamMay 20, 1202: A massive earthquake strikes Syria. Estimates of the death toll vary widely, from 30,000 to up to 1 million.

May 20, 1973: The U.K. Royal Navy sends three frigates to defend British fishing boats in waters claimed by Iceland in the ongoing "Cod Wars" between the two nations.

May 20, 2006: The last concrete is poured in the main wall of China's Three Gorges Dam (at right in 2011). The immense dam across the Yangtze River is authorized as a flood control and hydro energy project, but international critics say the dam is an environmental nightmare. China evacuates 1.3 million people whose homes will be flooded by the dam's reservoir.

Photo: ZUMA Press

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

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