This original postcard is from the 1933 Century Of Progress (Chicago World's Fair) which was held in Chicago. It is in excellent condition and the front features "The Sinclair Dinosaur at the Century Of Progress". The reverse side features a postcard format, which is unused. This postcard has a paragraph on the back that says "The Dinosaur Exhibit built by the Sinclair Refining Company at the 1933 World's Fair in Chicago is the first attempt to recreate out-of-doors a portion of the earth's surface as it existed 100 million years ago. The huge beast shown on this card is a Brontosaurus. He bulked 40 tons in life and was 70 feet long". This postcard measures approx. 5 1/2" x 3 1/2".