Throughout history, the search for salt has played an important role in society. Where there was no salt near, it was brought from distance. Thus, salt became one of the most important articles of early trade. Records show that in areas of scarcity, salt was traded ounce for ounce for gold. Roman’s major highway was called the via salaria, that is, the salt road. Along that road, roman soldiers transported salt crystals from the salts at ostia up the tiber river. In turn, they received a salarium or salary, which was literally money paid to soldiers it buy salt. The old saying “worth their salt,” which means to valuable, derives from custom of payment during the empire. The caravan trade of the sahara was also primarily an exchange of goods for salt. Slaves were often purchased with salt. Salt was so important in the middle ages that governments retained salt trade as a monopoly, or levied taxes on its purchase. By then, people’s social rank was demonstrated by where they sat at the table, above or below the salt.