<P> The archaeological sites of San Lorenzo Tenochtitlán can be visited Monday to Sunday, from 8: 00 to 15: 00 hours local time . </P> <P> The San Lorenzo site is well known for the multitude of stone sculptures displayed . Some of these sculptures depict supernatural deities, while others the flesh - and - blood embodiments on earth . Up to 124 stone sculptures have been discovered, and it is suspected that many more remain buried . The sculptures range in size, with the gigantic Colossal Heads weighing up to 28 tons . All the basalt used in this artwork originated at the Cerro Cintepec volcano in the Tuxtla mountains . These sculptures were not only done for aesthetic beauty, but also symbolized the awe - inspiring way that the Olmec viewed their deities . It also showed the power the rulers had, because a successfully delivery of a stone or finished sculpture involved complex organization and the ability to order extreme amounts of labor . </P> <P> In the 1960s, Michael Coe and Richard Diehl conducted excavations on San Lorenzo and surrounding sites, and defined eight major phases of occupation . The Ojochi (ca . 1750--1550 B.C.) and Bajío (ca . 1550--1450 B.C.) phases constituted the pre-Olmec Initial Formative sequence . In the Early Formative Chicharras phase (ca . 1450--1400 B.C.) more characteristically Olmec artifacts appear on the site . San Lorenzo rose to the height of its power in the San Lorenzo phase (ca . 1400--1000 B.C.). However, it suffered a decline in the beginning of the Middle Formative period . This period encompasses the Nacaste (ca . 1000--800 B.C.) and the Palangana (ca . 800--400 B.C.) phases . Its population declined further in the Late Formative Remplás phase (ca . 300--50 B.C.), and while there was occupation during the Early & Middle Classic periods, it was not reoccupied until late in the Villa Alta phase (A.D. 800--1000). </P> <P> At the top of the plateau of San Lorenzo, massive thrones, colossal heads, and smaller sculptures of humans, felines, birds, and supernatural monsters proclaimed the power of its rulers and its sacred source . Most of these sculptures were carved from imported basalt . The elites of San Lorenzo lived in large structures raised on low clay platforms amid the monuments that legitimized their authority . An elite residence named the "Red Palace" had earthen walls and floors, which were plastered with sand stained by hematite . Massive columns that were 4 metres (13 ft) tall and carved out of basalt supported the structure's roof, and L - shaped basalt benches are thought to have been used as step coverings . Blocks of bentonite clay and limestone have been found in the debris, and may have been used in the walls . Several structures had walls that were made of thick mud and 40 centimetres (16 in) thick, and lacked post-molds . They were evidently constructed using a rammed earth technique . Other structures employed bentonite masonry fixed with mud mortar . Floors were made of gravel or packed earth, or paved with bentonite blocks . </P>

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