Colombia/Peru/Brazil: Three Borders

Tri-border area on the Amazon, only accessible by boat or plane. Insane!! Perfect starting point for Amazon exploration :) And borderly awesome (Low Five!), visited three countries multiple times simultaneously in less than 24 hours! Oh, and since it's not quite clear where each photo was taken, a little guessing game for the keen observer: in which country do you think each photo was taken? I'll remain unusually comment and title-free ;)