This original postcard is from the 1933 Century Of Progress (Chicago World's Fair) which was held in Chicago. It is in very good condition but is slightly yellowed & stained and the front features the "Sinclair Dinosaur Exhibit". The reverse side features a postcard format, which is unused and a paragraph that says "The Dinosaur Exhibit built by the Sinclair Refining Campany at the 1933-34 World's Fair in Chicago is the first attempt to recreate out-of-doors a portion of the earth's surface & animal life as they existed 100 million years ago. Brontosaurus reproduced life-size is the largest animated in the world. In life he bulked 40 tons and was 70 feet long" and measures approx. 5 1/2" x 3 1/2".