Although Hong Kong is a modern city, it contains a unique geological environment and prehistoric archaeological heritage. Up to now, we have discovered more than 100 prehistoric heritage sites and nine prehistoric rock carvings. In addition to studying from a historical perspective, analysis of geological structure of the site, such as distribution and characteristics of rocks, can also provide further "evidence" for investigating prehistoric culture. This lecture will introduce Hong Kong's cultural development during the Stone Age from a geological point of view. What is the relationship between the patterns of stone carvings and the properties of rocks? Which type of rock is most suitable for making stone tools? Where is the origin of the stones? What are the impacts of stone tools and ornaments on the economy and culture? Which location in Hong Kong was previously an archaeological site for stone tools production? The speaker will discuss these issues with you one by one.