Classic period "Caana" at Caracol. It stands at 42 meters (140 feet) high. Altar 13 at Caracol. AD 830 The Classic period (c. AD 250900) was one of the peak of large-scale construction and urbanism, the recording of monumental inscriptions, and significant intellectual and artistic development, particularly in the southern lowland regions.[9] The people developed an agriculturally intensive, city-centered civilization consisting of numerous independent city-states some subservient to others.[8] This includes the well-known cities of Caracol, Tikal, Palenque, Copán, Xunantunich and Calakmul, but also the lesser known Lamanai, Dos Pilas, Cahal Pech, Uaxactun, Altun Ha, and Bonampak, among others. The Early Classic settlement distribution in the northern Maya lowlands is not as clearly known as the southern zone, but does include a number of population centers, such as Oxkintok, Chunchucmil, and the early occupation of Uxmal. During this period the Maya population numbered in the millions. They created a multitude of kingdoms and small empires, built monumental palaces and temples, engaged in highly developed ceremonies, and developed an elaborate hieroglyphic writing system.[10] The social basis of this exuberant civilization was a large political and economic intersocietal network (world system) extending throughout the Maya region and beyond to the wider Mesoamerican world. The political, economic, and culturally dominant core Maya units of the Classic Maya world system were located in the central lowlands, while its corresponding dependent or peripheral Maya units were found along the margins of the southern highland and northern lowland areas. But as in all world systems, the Maya core centers shifted through time, starting out during Preclassic times in the southern highlands, moving to the central lowlands during the Classic period, and finally shifting to the northern peninsula during the Postclassic period. In this Maya world system, the semi-peripheral (mediational) units generally took the form of trade and commercial centers.[11] The most notable monuments are the stepped pyramids they built in their religious centers and the accompanying palaces of their rulers. The palace at Cancuén is the largest in the Maya area, but the site has no pyramids. Other important archaeological remains include the carved stone slabs usually called stelae (the Maya called them tetun, or "tree-stones"), which depict rulers along with hieroglyphic texts describing their genealogy, military victories, and other accomplishments.[12] The Maya civilization participated in long distance trade with many of the other Mesoamerican cultures, including Teotihuacan, the Zapotec, and other groups in central and gulf-coast Mexico. In addition, they had trade and exchanges with more distant, non-Mesoamerican groups, for example the Taínos of the Caribbean islands. Archeologists have found gold from Panama in the Sacred Cenote of Chichen Itza.[13] Important trade goods included cacao, salt, seashells, jade, and obsidian. This is copan in my country