Chancel, St. Peter's Cathedral, Regensburg, Austria
Left to right: Peter (key in left hand, bald spot on top of head), Andrew (wild hair, cross in left hand), John (chalice barely discernible in right hand), Paul (sword, pointy beard).
I have digitally moved the second pair of windows to the left to fit them on the screen. The correct space between the two pairs can be examined on the full-resolution page linked below.
Read more about full resolution
Read more about St. Peter, St. Andrew, St. John the Evangelist, and St. Paul.
Photographed at the cathedral by Richard Stracke, shared under Attribution-NonCommercial-ShareAlike license.