Take a look at this website, for the Canadian War Plane Heritage Museum, which has the "highest hours in the air " DC 3 anywhere in the world. Built in 1937, and known as "Canucks Unlimited ".

Go here : CANADIAN WARPLANE HERITAGE

Contrary to what you said, there are number of DC3;s still flying on a daily basis, for FORD Aviation ( Yes that FORD ) out of Detroit, Michigan. And here in Toronto, Millard Aviation has at least 3 still flying air freight to northern Canada. In the third world they are still seen and used.

Jim Bunting. Toronto. Ontario, Canada.