The Olmec civilization flourished roughly between 1200 BC and 400 BC, an era commonly known as Central America's Formative Period. Sites containing traces of the Olmec civilization are found mainly on the southern coast of the Gulf of Mexico, specifically in the states of Veracruz and Tabasco. Although the Olmecs did have a system of writing, only few of their inscriptions are available to archaeologists at present. Moreover, there is not enough continuous Olmec script for archaeologist to decipher the language. As a result, much of what we know about the Olmec civilization is dependent on the archaeological evidence.