During construction work in Aegerten, in Switzerland’s canton of Bern, archaeologists made a remarkable discovery: the remains of a Roman-era wooden bridge estimated to be around 2,000 years old. Excavation efforts revealed more than 300 oak piles—remarkably well preserved in the waterlogged conditions of what was once the riverbed of the Zihl (also known as the Thielle).

This bridge formed a vital part of the Jura Transversal, a Roman transport network that connected waterways and roads across the region. It once stood at the gateway to the small Roman settlement of Petinesca—modern-day Studen—serving as an important crossroad of trade and travel.

Researchers from the Archaeological Service of the Canton of Bern took samples from the oak piles for analysis in laboratories. Dendrochronological (tree-ring) examination revealed that the bridge underwent several rounds of repair and reconstruction over centuries. The earliest construction dates back to around 40 BC, shortly after Rome’s conquest of the Celtic tribe Helvetii (or Helvetians), while the latest modifications date from 369 AD, during the reign of the Roman Emperor Valentinian I—suggesting the bridge remained in use for more than four centuries.

Beyond the structural remains, the archaeologists uncovered a variety of everyday artifacts in the former riverbed—items that offer a glimpse into the daily lives of Roman-era inhabitants. Among these finds were shoe nails, axes, a fishing trident, keys and coins. Notably, a large wooden plane reinforced with iron was also preserved, its survival attributed to the oxygen-poor damp soil that shielded it from decay.

This discovery provides not only tangible evidence of Roman infrastructure in the region but also rich insights into daily life, craft, and mobility in Roman Switzerland. It stands as one of the most significant Roman-era archaeological finds in the Bern area in recent decades.