The Princess Bride (1987)

How could anyone not love this duel between Inigo Montoya and the man in black atop the Cliffs of Insanity? Mandy Patinkin and Cary Elwes learned to fence both right-handed and left-handed for this movie

Note the references to Ridolfo Capoferro, Camillo Agrippa, Girard Thibault and Rocco Bonetti, actual 16th and 17th century fencing masters.