The Classic Period, which began around A.D. 250, was the golden age of the Maya Empire. Classic Maya civilization grew to some 40 cities, including Tikal, Uaxactún, Copán, Bonampak, Dos Pilas, Calakmul, Palenque and Río Bec; each city held a population of between 5,000 and 50,000 people. At its peak, the Maya population may have reached 2,000,000.  

Excavations of Maya sites have unearthed plazas, palaces, temples and pyramids, as well as courts for playing the ball games that were ritually and politically significant to Maya culture. Maya cities were surrounded and supported by a large population of farmers. Though the Maya practiced a primitive type of "slash-and-burn" agriculture, they also displayed evidence of more advanced farming methods, such as irrigation and terracing.

The Maya were deeply religious, and worshiped various gods related to nature, including the gods of the sun, the moon, rain and corn. At the top of Maya society were the kings, or "kuhul ajaw" (holy lords), who claimed to be related to gods and followed a hereditary succession. They were thought to serve as mediators between the gods and people on earth, and performed the elaborate religious ceremonies and rituals so important to the Maya culture.

The Classic Maya built many of their temples and palaces in a stepped pyramid shape, decorating them with elaborate reliefs and inscriptions. These structures have earned the Maya their reputation as the great artists of Mesoamerica. Guided by their religious ritual, the Maya also made significant advances in mathematics and astronomy, including the use of the zero and the development of a complex calendar system based on 365 days. Though early researchers concluded that the Maya were a peaceful society of priests and scribes, later evidence--including a thorough examination of the artwork and inscriptions on their temple walls--showed the less peaceful side of Maya culture, including the war between rival Mayan city-states and the importance of torture and human sacrifice to their religious ritual.

Serious exploration of Classic Maya sites began in the 1830s. By the early to mid-20th century, a small portion of their system of hieroglyph writing had been deciphered, and more about their history and culture became known. Most of what historians know about the Maya comes from what remains of their architecture and art, including stone carvings and inscriptions on their buildings and monuments. The Maya also made paper from tree bark and wrote in books made from this paper, known as codices; four of these codices are known to have survived.