What is the main road that ran on the east-west axis in a Roman city?

The term that refers to the main road running along the east-west axis in a Roman city is "Decumanus." In Roman urban planning, cities were often laid out in a grid pattern with two main thoroughfares: the cardo, which ran north to south, and the decumanus, which ran east to west. This layout not only facilitated trade and movement within the city but also contributed to the organization and functionality of urban life.

The decumanus served as a key route through Roman cities, linking various important structures and areas, including forums, temples, and marketplaces. Its significance is highlighted in archaeological sites like Pompeii and Herculaneum, where the remains of these roadways can still be observed today.

By understanding the roles of these different pathways, one can appreciate how Roman engineering and urban planning influenced the growth and organization of their cities. The other terms in the options refer to different aspects of Roman infrastructure or specific routes but do not denote the primary east-west road characteristic of Roman city layouts.