The Copán Archaeological Site, run by the Honduras Institute of Anthropology and History, is one of the most intensively excavated Mayan sites in the world. The Principal Group covers the core of the ancient city: the Acropolis (a massive complex of superimposed temples on an artificial platform), the Great Plaza (surrounded by intricate stelae), the East and West Courts, and the Hieroglyphic Stairway.
The Hieroglyphic Stairway is 63 steps wide and inscribed with approximately 2,200 individual hieroglyphs — the longest known Mayan inscription. The stairway was built by King Smoke Shell around 755 AD to record the history of the Copán dynasty; earthquake damage and reconstruction work have made parts of the inscription difficult to read. An adjacent tunnel system, open to visitors for an additional fee, exposes the interior of earlier temples including Temple 16's predecessor, showing how the Mayan builders encased earlier structures in larger new ones.