There is not an exact finish date for the Great Wall of China and some believe it is still not finished. Some pieces have fallen and may be fixed in the future. The Great Wall of China was not built all at one time. Work on the wall began in 7th century BC. Pieces were built at different time periods and took over 1,700 years to get it to the final size that it is today. The Great Wall is listed at one of the Seven Wonders of the World.