Archaeological studies in Hong Kong began in the 1920s and have uncovered evidence of ancient human activities at many sites along the winding shoreline, testifying to events spanning more than 6 000 years. The interpretation of these events is still a matter of academic discussion. Archaeologically, Hong Kong is but a tiny part of the far greater cultural sphere of South China, itself as yet imperfectly known.

Despite suggestions that local prehistoric cultures developed out of incursions from North China or Southeast Asia, a growing number of scholars believe that the prehistoric cultures within the South China region evolved locally, independent of any major outside influences. There is little dispute, on the other hand, that these earliest periods, from 4000 BC, must be seen within the framework of a changing environment in which sea levels rose from depths of 100 metres below the present — inexorably submerging vast tracts of coastal plain and establishing a basically modern shoreline and ecology to which human groups had to adapt if they were not to perish.

Archaeological excavations have revealed two main Neolithic cultures lying in stratified sequence. The final phase of Hong Kong's prehistory was marked by the appearance of bronze about the middle of the second millennium BC. Bronze artefacts seem not to have been in common use, but fine specimens of weapons, knives, arrowheads and halberds, and tools such as fish hooks and socketed axes have been excavated from Hong Kong sites. There is evidence, too, in the form of stone moulds from Kwo Lo Wan on the original Chek Lap Kok Island, Tung Wan and Sha Lo Wan on Lantau Island and Tai Wan and Sha Po Tsuen on Lamma Island, that the metal was actually worked locally.

The pottery of the Bronze Age is decorated with designs, many of which are reminiscent of the geometric patterns of the late Neolithic period, but with their own distinctive style, including the 'Kui-dragon' or 'double F' pattern so characteristic of the region during this period.

Early Chinese literary records make references to maritime people known as 'Yue' occupying China's southeastern seaboard. It is probable, therefore, that at least some of Hong Kong's prehistoric inhabitants belonged to the 'Hundred Yue', as this diverse group of peoples was often called.

The discovery of a prehistoric burial ground at Tung Wan Tsai North on Ma Wan Island in 1997 shed light on the ethnicity of prehistoric inhabitants in Hong Kong. Among the 20 burials discovered, 15 yielded human skeletal remains, seven of which were well preserved. Study of the human bones revealed that these early inhabitants were Asian Mongoloid with characteristics of a tropical racial group.

A Neolithic stone-working site discovered at Ho Chung, Sai Kung, in 1999 was also of significance. Scattered around an activity floor, which covered about 200 square metres, were a number of stone cores, flakes, chipped stone tools such as oyster picks, carving tools and polished implements that included adzes, rings and slotted rings. The artefacts provide valuable data for the study of the stone-working technology of Hong Kong's Neolithic inhabitants.

To save the archaeological heritage from destruction by impending road construction, a joint local and Mainland team carried out a rescue excavation in Sha Ha, also in Sai Kung, between October 2001 and September 2002. This team, comprising experts from the archaeological institutes of Shaanxi, Hebei, Henan and Guangzhou as well as the Antiquities and Monuments Office, was the largest ever mobilised in Hong Kong. Important discoveries included artefacts and archaeological features of the Neolithic Period and the Bronze Age as well as the Tang/Song and Ming/Qing dynasties. These findings not only helped portray the chronology of the local archaeological cultures, but also provided important clues to trace the prehistoric society and settlement patterns of the Pearl River Delta.

Interesting archaeological features, almost certainly made by those people, include the rock carvings, most of which are geometric in style, at Shek Pik on Lantau Island, on Kau Sai Chau, Po Toi, Cheung Chau and Tung Lung Chau, and at Big Wave Bay and Wong Chuk Hang on Hong Kong Island.

The military conquest of South China by the North during the Qin (221-207 BC) and Han (206 BC-AD 220) dynasties must have brought increasing numbers of Han settlers into the region and exerted a variety of influences on the indigenous populations. Testimony to this is the excavation of coins of the Han period, but the outstanding monument to this turbulent period must undoubtedly be the fine brick-built tomb uncovered at Lei Cheng Uk, in Sham Shui Po, in 1955, with its array of typical Han tomb furniture, dateable from the early to middle Eastern Han period. Rescue excavations at Pak Mong on Lantau Island, on Kau Sai Chau, at Tung Wan Tsai on Ma Wan Island and at So Kwun Wat in Tuen Mun all yielded considerable quantities of Han Dynasty artefacts in well-stratified sequences, as well as four pottery pots discovered from the drainage works site at Mong Kok. These included pottery vessels of various kinds, iron implements and a large quantity of bronze coins.

Archaeological remains from later historic periods are still relatively rare. Excavations have thrown welcome light on one aspect of life in Hong Kong during the Tang Dynasty (AD 618-907) through a study of the dome-shaped lime kilns which are almost ubiquitous features of Hong Kong's beaches. Lime was a valuable commodity useful for caulking and protecting wooden boats against marine organisms, water-proofing containers, dressing the acid soils of agricultural fields, building, and salt production among other purposes. It clearly played an important role in the economy of the period.

Strong traditions link Hong Kong with the events surrounding the Mongol incursions and the concluding chapters of the Song Dynasty in the 13th century AD. Several local finds are from this period: the Sung Wong Toi inscription, now relocated near the entrance to the former Hong Kong International Airport in Kowloon; the Song inscription in the grounds of the Tin Hau Temple at Joss House Bay; caches of Song coins from Shek Pik, Mai Po and Kellett Island; and celadons of Song type from various sites, especially Nim Shue Wan and Shek Pik on Lantau Island and Ngau Hom Shek in Yuen Long.

Studies are beginning to shed fresh light on events in Hong Kong during the Ming (AD 1368-1644) and Qing (AD 1644-1911) dynasties. These include an analysis of considerable quantities of Ming blue-and-white porcelain collected and excavated from Penny's Bay, Lantau. It is very fine quality export ware of the kind that found its way to the courts of Southeast Asia and further west, and dates from the first decades of the 16th century AD. During another excavation in 2001, more Ming remains were retrieved, including building foundations and structures suggesting the presence of a Ming settlement in Penny's Bay. Archaeological investigations at the ancient kiln site at Wun Yiu in Tai Po suggested that potters probably began to manufacture blue-and-white wares locally early in the Ming Dynasty. The porcelain industry continued until the early 20th century, spanning a period of 500 years. The rescue excavation at So Kwun Wat in 2000 yielded a Ming Dynasty cemetery and more than 30 burials were found. The burial items — which include porcelain wares, bronze coins and iron implements — shed light on the life of local inhabitants in the Ming Dynasty.

The excavation of the Qing Dynasty fort on Tung Lung Chau has revealed fascinating details of the internal arrangements of the fortification and everyday utensils of the remote garrison during the final stages of Imperial China. Archaeological investigations at the Kowloon Walled City site also uncovered remnants of the old garrison wall and the two stone plaques above the original South Gate, which bore the Chinese characters 'South Gate' and 'Kowloon Garrison City', respectively.