China's Palace Museum, located inside the Forbidden City, announced on Wednesday that a seven-year inventory, which began in 2004, reveals the museum's collection includes 1,807,558 objects, providing the first accurate appraisal of the size of the museum's collection.

At a press conference in Beijing, museum officials said the inventory is the first accurate and comprehensive accounting of all museum pieces since the museum opened in 1925 in the imperial palace of China's last two dynasties - the Ming (1368-1644) and the Qing (1644-1911).

The officials said about 93 percent of these objects are of great cultural value.

The difficulty in determining the exact number of collected objects was due to the immensity of the vast holdings of the imperial collections of paintings, calligraphy, ceramics and decorative objects, as well as a result of the transferring of the collection during the Sino-Japanese War.

The Forbidden City was named a UNESCO World Heritage site in 1987.