and kidnapping for ransom. For Romans, the seas were more or less clear of pirates due to the Roman military, although the fear of shipwreck by storm was greater, and often referenced in poetry and song. Passage by ship was considerably more pleasant than passage by land, but was not available throughout the year due to changes in tides and other weather conditions. Land travel The earliest notable road system in the ancient Mediterranean world was the Royal Road. The most extensive incarnation of the system was unified and organized under Darius I, ruler of the Achaemenid Empire in the 5th century BCE. It was built from connecting and upgrading older systems, and was used to enable rapid communication and transportation throughout the empire, as well as the collection of taxes. Generally, other contemporary roads were not paved or well maintained, making land travel both on foot and horseback arduous and time-consuming. Greece Greek roads were poorly developed due to the fragmentation of Greek society at the state level, and due to the extreme cost of constructing roads in Greece's mountainous terrain. At least in Athens, when built, roads were funded through special taxes on wealthy. Some roads were difficult to traverse even on foot, and most could not be traversed with the heavy wagons built to haul goods. Notable exceptions were the roads between major cities and nearby sanctuaries and holy sites, which were built to endure all weather. However, no portion of the Greek highway system included state-sponsored way stations or milestones, as found later in Rome. There was danger of violence on Greek roads. For the same reasons that roads in Greece were poorly and rarely constructed, there was essentially no oversight by official forces, and as such travelers were prone to being accosted by highwaymen. As such, having a large entourage was useful for protection, and the transportation of valuables was risky. Rome Roman roads were extensive, largely to facilitate the transportation of the military. They suffered from lack of maintenance, at least during the Roman Republic due to the fact that more visible projects (new city-centric construction, such as aqueducts, and arena games) took precedence. The roads were built with few resources and had to be built to function in a variety of geographical and seasonal conditions. As Roman roads radiated away from towns, they became less elaborate and were sometimes paved with gravel, or