Not, "just to be different"; but because I'm fairly certain you're going to receive a number of responses, nominating great, and/or very famous and popular classical compositions: Gounod's "Faust"; Rossini's "William Tell"; Liszt's "Faust Symphony"; etc.
But tangentially, to focus on eliciting a greater and much deserved awareness of who in my opinion, is one of, if not the greatest heroine of all time: Joan of Arc.
A new film has came out recently extolling the courage and great bravery of this country's Amelia Earhart. And not to disparage her, but her accomplishments, heroism, again in my humble opinion, pales when compared to that of the tragic Joan. Schiller wrote a play about "The Maid": http://en.wikipedia.org/wiki/The_Maid_of_Orleans_(play)
To which Tchaikovsky wrote an opera, based on a variation of the original text, and is my choice to commemorate the 250th anniversary of Schiller's birth. Granted, not a master-piece, perhaps even at best, second rate opera; the point being that each of these great artist in their respective fields of endeavor, strove in their own way to memorialize her. And for that, I commend them both.
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. A You Tube video of the finale to Tchaikovsky's "The Maid of Orleans": http://www.youtube.com/watch?v=2sbPlwJnIK0
Alberich