Final answer:
Proximity to a seaport was important to Roman trade because shipping by sea was less expensive than by land, and access to a seaport facilitated trade and allowed the Romans to import goods from distant regions.
Step-by-step explanation:
Proximity to a seaport was important to Roman trade because shipping by sea was less expensive than by land. The Romans built a strong network of roads, but shipping by sea was still more cost-effective. Access to a seaport facilitated trade and allowed the Romans to import goods from distant regions. Italy, where Rome was located, had several fine seaports like Ostia, which played a crucial role in trade. Italy itself produced goods that were traded around the Mediterranean, and Italy dominated the western trade routes.