there are many obvious classics like Cliffhanger
or Captain Kirk in Star Trek
; then some obscure solos like the Monster's climb of the castle wall in Young Frankenstein
....my vote goes to Jon Voight's midnight solo out of the river gorge in Deliverance
Matt Damon free solo down climbing the embassy in The Bourne Identity
that and Wesley's Free solo in the second act of The Princess Bride
ahhh dang it, one more, Leonidas Free solo & dyno in 300
Here's the Leonidas free solo. first minute of video.