Nikola Tesla's laboratory, Colorado Springs. Croatian-born physicist Tesla (1856-1943) moved to Colorado Springs, Colorado, USA, in May 1899, where he built a large barn-like laboratory (seen here) with a 61 metre pole protruding from the roof. At the top of the pole was a 79 centimetre wooden ball wrapped in copper foil. Over the next eight months, Tesla carried out some of his most important work including discovering the existence of stationary waves in the earth and creating the largest display of man-made lightning to this day. Tesla left Colorado Springs in January 1900. The laboratory was eventually dismantled and its contents sold to pay outstanding debts.