The National Register of Historic Places is a database of many of the historic sites in the country that are worth preserving.  As of 2012, there are over 2,000 entries of these places in Tennessee.  While I wish this was an exhaustive map of every single entry in Tennessee, that simply isn't possible.  Some are inaccessible, some are privately owned and restricted, while others simply have nothing to photograph.  On the other hand, some of these are historic districts that include multiple buildings.  Plus, this is an ever-expanding list where new entries could be added every week!  I am going to speculate that the map above represents about 15% of the listings in the state.  While I will never see them all, the list of the ones I have visited will continue to grow, so think of these as the highlights! See the entire list here.