 It can be delimited by a line running from the Laguna de Términos on the Gulf coast through to the Gulf of Honduras on the Caribbean coast.It incorporates the modern Mexican states of Yucatán, Quintana Roo and Campeche, the eastern portion of the state of Tabasco, most of the Guatemalan department of Petén, and all of Belize.Most of the peninsula is formed by a vast plain with few hills or mountains and a generally low coastline.