Ancient Iranians built an early network of roads, including the Royal Road.

The Royal Road was built to connect the vast Achaemenid Empire. It stretched about 2,700 kilometers (almost 1,700 miles) from Sardis in the west to Susa in the east. This road helped messengers, traders, and soldiers travel quickly across the empire. It was one of the earliest examples of a long, built road system, showing the empire's advanced organization.