The maritime Silk Road was a conduit for trade and cultural exchange between China's south-eastern coastal areas and foreign countries. There were two major routes: the East China Sea Silk Route and the South China Sea Silk Route .
The East China Sea Silk Route mainly went to Japan and Korea. It dates back to the Zhou Dynasty (1112 BC) when the government sent some Chinese people to Korea to teach its people farming and sericulture, departing from the port of Bohai Bay, Shandong Peninsula.
From that time, the skills and techniques of raising silkworms, silk reeling and weaving were introduced into Korea slowly via the Yellow Sea.
When Emperor Qin Shi Huang united China (221 BC), many people from the States of Qi, Yan and Zhao fled to Korea and took with them silkworms and raising technology, which sped up the development of silk spinning in Korea.
During the Sui and Tang dynasties, Japanese envoys and monks travelled to China frequently. They brought back the blue damask silks that they got in Taizhou, Zhejiang Province, which served as samples. Since the Tang Dynasty, silk products from Jiangsu and Zhejiang provinces were directly transported to Japan by sea, and the silk products formally became the commodities.
In the Song Dynasty, lots of silk products were exported to Japan. In the Yuan Dynasty, the government set up Shi Bo Si (市舶司) in many ports, such as Ningbo, Quanzhou, Guangzhou, Shanghai, Ganpu (澉浦), Wenzhou, and Hangzhou, in order to export the silk products to Japan.
Shi Bo Si's Oceangoing and Marketing Department, was set up in each port to administrate foreign economy-related affairs by sea during the dynasties of Tang, Song and Yuan, and the early part of the Ming Dynasty.
The maritime Silk Road fell into decline because of the Haijin policy of the Qing Dynasty. The Haijin policy (海禁) was a ban on maritime activities imposed during the Ming and Qing dynasties.
The South China Sea Silk Route was an important conduit for China's exchanges with the outside world. The South China Sea Silk Route got its name for being centered around the South China Sea, and its starting points at that time were mainly in Guangzhou, Quanzhou and Ningbo.
Like the East China Sea Silk Route, it was first used in the Qin and Han dynasties, increased its popularity from the Three Kingdoms Period to the Sui Dynasty, flourished in the Tang and Song dynasties, and began to wane in the Ming and Qing dynasties.
Before the Sui Dynasty, the maritime Silk Road was the most famous transportation route since the overland Silk Road run, and then the maritime Silk Road became a secondary alternative to it.
During the period of the Sui and Tang dynasties, the overland Silk Road was interrupted by wars in the western areas, giving place to the maritime Silk Road.
In the late Tang and Song dynasties, technological advances in shipbuilding and navigation led to the opening of new sea lanes to Southeast Asia, Malacca, the Indian Ocean, the Red Sea and the continent of Africa, which made the maritime Silk Road rise again.