Inconceivable! From a longer list on Buzzfeed.
Director Rob Reiner auditioned over 500 women for the role of Buttercup, including Courtney Cox, Meg Ryan, Uma Thurman, and Whoopie Goldberg.
The Princess Bride was almost made into a movie in the ’70s, and a then-unknown Arnold Schwarzenegger was seriously considered to play Fezzik.
Reiner’s first choice to play Vizzini was Danny DeVito, but the role ultimately went to Wallace Shawn.
Neither Cary Elwes or Mandy Patinkin had any sword-fighting
experience before filming. Both trained rigorously, and every frame of
Inigo and Westley’s sword fight on The Cliffs of Insanity is actually
the two actors.
Rob Reiner offered Mandy Patinkin any role he wanted in The Princess Bride.
Patinkin chose Inigo partly because his own father died a few years before filming, and for motivation he would tell himself that if he caught the six-fingered man, his own father would come back.
Mandy Patinkin’s favorite line in the movie is when Inigo says, “I
have been in the revenge business so long, now that it’s over, I don’t
know what to do with the rest of my life.”
The first scene Robin Wright filmed was her dress catching fire in
the Fire Swamp. The fire is real, but the skirt was made of
flame-retardant cloth. William Goldman, who wrote the book and the
screenplay for The Princess Bride, was on set at the time and screamed,
“Her dress is on fire!” ruining the shot.
Billy Crystal wanted Miracle Max to look like a cross between his own grandmother and former Yankees manager Casey Stengel.
Crystal filmed the role of Miracle Max over three days for 10 hours a day, and never made the same joke twice.
Rob Reiner would laugh so much at Crystal’s lines he would have to leave the room during filming.
Goldman decided Rob Reiner was the right man to direct The Princess Bride only after he saw This Is Spinal Tap.
Reiner once ran into mob boss John Gotti and six of his men outside a New York restaurant. One of them looked at him and said, “You killed my father, prepare to die!” then burst out laughing.
A body double was used for the scene when Westley jumps on Fezzik’s back because André the Giant had severe back issues.
During fight rehearsal for Inigo’s big showdown with Count Rugen, Mandy Patinkin accidentally stabbed Christopher Guest in the thigh.
The final scene of the movie was originally going to be The Grandson looking out his window and seeing the four heroes, sitting on white horses, waving from below. Reiner decided against it and reshot the final scene.