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. In 108 BC, 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. Three Kingdoms period (c. 1st century BC-668) Common architecture In the Three Kingdoms Period, some people lived in pit-houses while others lived in raised-floor buildings. For example, the Hanseong (Hangul: 한성, 漢城; an eastern part of Seoul and western part of Hanam city in Gyeonggi Province) Baekje settlement of Seongdong-ri in Gyeonggi Province contained only pit-houses, while the Silla settlement of Siji-dong in Greater Daegu contained only raised-floor architecture. Fortress architecture Goguryeo, the largest kingdom among the Three Kingdoms of Korea, is renowned for its mountain fortresses built horizontally and vertically along the incline of slopes. One of the well-preserved Goguryeo fortresses is Baekam fortress (白巖城) constructed before 6th century in present-day South-West Manchuria. A Chinese historian noted, "The Goguryeo people like to build their palaces well." Patterned tiles and ornate bracket systems were already in use in many palaces in Pyongyang, the capital, and other town-fortresses in what now is Manchuria. Religious architecture The construction of Buddhist temples was undertaken after Buddhism was introduced in Korean Goguryeo in 372 by way of northern China. A series of excavations in 1936-1938 unearthed the sites of several major temples near Pyongyang, including those in Cheongam-ri, Wono-ri and Sango-ri. The excavations disclosed that the temples were built in a Goguryeo style known as "three Halls-one Pagoda," with each hall in the east, west and north, and an entrance gate in the south. In most cases, the central pagodas had an octagonal plan. Palace buildings appear to have been arranged in this way as well. Baekje was founded in 18 BC and its territory included the west coast of the ancient Korea. After the fall of Nangnang County under the Han dynasty in China, Korean Baekje established friendships with China and Japan. Great temples were built during this time. The earliest stone pagoda of the Mireuksa Temple in Iksan county is of particular interest because it shows the transitional features from a wooden pagoda to a