During the late 7th century, Maya engineers constructed the longest Maya bridge known to exist in the ancient world. It spanned 113 meters across the Usumacinta River and was designed to allow residents of Yaxchilan to reach their villages and farms.

The Maya Bridge – The Longest Bridge of the Ancient World?

Here’s more from the discoverer of the Maya bridge, James O’Kon:

The Maya city of Yaxchilan is sited within a giant omega of the Usumacinta River. This circular bend in the river developed a 3.2 kilometer wide land mass within the inner curve of the river. This protected area, formed within the confines of the inner curve of the river, created a natural fortress for the city. However, the river is in a flood state for six months of the year, and during the rainy season the broad and swiftly flowing waters isolated the city from access to its domain across the river.

In order to survive as a viable urban center, this ancient city required a dependable year-round way to cross the river. While the site had been studied by archaeologists since 1882, the need for a bridge crossing was not considered as a necessity by archaeological studies. The ancient ruins that were the clues to the existence of this lost landmark of Maya Engineering were hiding in plain sight…The need for a permanent lifeline to insure the survival of the city during the flood season was overlooked by archaeologists until James O’Kon carried out a series of expeditions, forensic engineering investigations, archaeo-engineering analysis, remote sensing, and computer modeling of this structure lead to the digital re-construction of the bridge. Constructed in the late 7th century, landmark three-span suspension bridge crossed from the city center over the Usumacinta River to the north side where the villages and farms were located…