With its rapid development in the past two decades, the Pearl River Delta has become one of the most developed regions in China. During this period, an important corridor between Hong Kong and Guangzhou has emerged and shaped the spatial structure of the region. The growth of this region has been greatly marched with the twin poles of Guangzhou and Hong Kong, and the economic and social development has taken place in a corridor between these two metropolises. This paper provides an analysis of the significance of this corridor in terms of its infrastructure, population, land use, and economic development. Massive infrastructure construction in the corridor has played an important role in its development. The corridor has high-frequent transport, and each transport mode has contributed in a different way to the process of development of the corridor. With high land use intensity and high population density, it is developing the characteristics of a megalopolis. As a pathway of connection between Guangzhou and Hong Kong, the corridor includes not only physical infrastructure, such as roads, railways and airports, but also logistics operations, human resources, information and capital, which plays important roles in accelerating business development. It demonstrates how this Main Street has become one of the most important factors in regional development.