Ombra mai fu is the opening aria from the 1738 opera Serse by George Frideric Handel.

The opera was a commercial failure, lasting only five performances in London after its premiere. In the 19th century, however, the aria was rediscovered and became one of Handel's best-known pieces.

http://www.youtube.com/watch?v=iHhiKTYOP7o

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http://www.youtube.com/watch?v=iHhiKTYOP7o