Show a Folder's Full Path in Finder's Title Bar [Mac Tip]
lifehacker.com/5102717/show-a-folders-full-path-in-finders-title-bar
From the page
Saved with the link. Notes from 2007 to 2016 are mostly the page's own words, so this is probably an excerpt.
By default Mac OS X's Finder displays only the current folder name in its title bar, but if you'd like a little more detail, The Unofficial Apple Weblog details how to enable path view in Finder to...