Proto–Three Kingdoms Period (c. 1st-2nd century BCE to 3rd-4th century CE)
Archaeological evidence of ondol(온돌), the Korean floor panel heating system, was found in the architectural remains of early Protohistoric period.[1]
According to Chinese text Sanguo Zhi, it recorded the existence of three types of prehistoric dwellings in Korea: pit houses, log houses and elevated houses. Only the remains of pit houses have been identified, however. Pit houses consisted of a 20–150 cm deep pit and a superstructure of grass and clay supported by a tripod-like frame made of timber to provide protection from the wind and rain. Pit houses of the Neolithic period had circular or oval pits about 5–6 meters in diameter with a hearth at the center. Most of the early ones were located on hills. As these dwellings moved down nearer to rivers, the pits became rectangular in shape as well as larger, with two separated hearths.[2] In 108 BCE, the Chinese commanderies was established after the destruction of Gojoseon. Official buildings of this period were built of wood and brick and roofed with tiles having the features of Chinese construction.