This really IS a creature! What is it?!

This blog is about all creatures great and small  (at http://roxannerustand.blogspot.com if you are reading this on Facebook) though that usually means pets, horses, and other familiar animals.  But this is creature I found on the side of our barn.  Looks like it is related to the dragon flies, given its wings, but it was huge and unlike anything I'd ever seen before...a little over 3.5  inches long.  Do you know what it is?!