"Zheng He's Nautical Charts" is the earliest extant nautical atlas in the world.

"Zheng He's Navigation Chart" was originally called "The Map of Sailing from Bao Shipyard and Leaving the Water from Longjiang Pass to Foreign Countries". This map is a record of Zheng He's voyage to the West, and was completed between the first year of Hongxi and the fifth year of Xuande.

"Zheng He's Nautical Charts" ***20 pages of nautical maps, 109 needle routes, and 2 pages of 4 ocean-crossing star charts. The nautical map is 20.3 cm high, 560 cm long, and contains 500 place names. The whole map starts from Nanjing and reaches as far as Manbasa (now Mombasa, Kenya) on the east coast of Africa. The map indicates the orientation, distance and depth of the Asian and African countries that the route passes through, as well as the direction and height of the navigation star. Wherever there are rocks or shoals, they are also noted.

The drawing process of "Zheng He's Navigation Chart":

The time when the painting was produced is unknown. One theory was written after Zheng He's sixth voyage to the West, when all the officers and soldiers on the voyage were guarding Nanjing. At that time, Emperor Xuanzong and Zhu Zhanji of the Ming Dynasty were planning to sail to the Western Ocean again. In addition, the pause was long and they had no time to organize. Therefore, they comprehensively compiled the previous voyages of Zheng He's fleet and drew a complete map of the Western Ocean. This is for This work was compiled collectively by Zheng He's mission to meet the needs of his voyages to the West.

The route drawn in this painting is consistent with the route of Zheng He’s main fleet in his seventh voyage to the West. It may be a work after the seventh voyage, but the drawing should not be later than the 15th century. middle leaf. In the late Ming Dynasty, Mao Yuanyi cut the picture into twenty sub-pictures (forty pages) and compiled it into the fifth part of "Wu Bei Zhi", "Zhan Du Zai", and tied it under "Du·Navigation". There are also two (four pages) "Piloting the Stars across the Ocean" attached to the nautical charts to explain the rules of star chart navigation.

Reference for the above content: Baidu Encyclopedia-Zheng He Navigation Chart