What is the meaning of "gold in the world"?

Cui Rongchuan, the Book of the Old Tang Dynasty: "There are many boats in Tianjin all over the world, bypassing Bahan, which used to refer to Fujian and Vietnam, seven rivers and ten miles, three rivers and five lakes, and controlled Heluo, including Huaihai and Hongge giant ships, with thousands of ships and constant exchanges."

It means; Around the world, ships and navigation gather together, which means that water transportation is very developed and there are many ships coming and going, which promotes economic development.

Extended content:

There are 200 volumes of Old Tang Book, including 20 volumes of Ji, 30 volumes of Shi Lu and Biography 150. Originally named Tang Shu, the New Tang Shu compiled by Song Qi and Ouyang Xiu was renamed Old Tang Shu after its publication, and the time should be in the Southern Song Dynasty. The compilation of the Book of Old Tang Dynasty is not far from the demise of the Tang Dynasty, and the sources of information are also relatively rich. The Tang Dynasty (AD 6 18-907) was an important period of feudal society in China. The Book of the Old Tang Dynasty, which was officially edited by the Five Dynasties and the Jin Dynasty, is the earliest existing historical book that systematically records the history of the Tang Dynasty.