text:  The <unk> civilization developed in the lowlands of southeastern Mexico between 1500 and 400 BC . The <unk> <unk> lies on the Gulf Coast of Mexico within the states of Veracruz and <unk> , an area measuring approximately 275 kilometres ( 171 mi ) east to west and extending about 100 kilometres ( 62 mi ) inland from the coast . The <unk> are regarded as the first civilization to develop in <unk> and the <unk> <unk> is one of six <unk> of civilization worldwide , the others being the <unk> <unk> culture of South America , the <unk> culture of China 's Yellow River , the Indus Valley Civilization of south Asia , the civilization of ancient Egypt and the <unk> civilization of ancient Iraq . Of these , only the <unk> civilization developed in a lowland tropical forest setting . 
  