This archway from the Terminal Classic era had collapsed when discovered by archeologists probably because of the corbeled arch. The Mayans did not use keystones to support their stone spans. Arco Sobre el Sacbé was reconstructed during the 1980s by the Mexican National Institute of Anthropology and History. It spans a path called a sacbé. These “white roads” were constructed with slabs of limestone. They linked the major sections of the ancient city.