This paper aims to address and discuss the measurement of within-country accessibility by computing travel times for Italy. Typically, domestic accessibility is measured at the municipal level, the smallest unit of analysis used in official national statistics; however, this territorial division may lack the granularity needed to capture specific variations within each unit. Conversely, supranational accessibility leverages finer information; however, if collected worldwide, global satellite and geocoded data may struggle with fine-grained accuracy within a country. To tackle these issues, we propose and analyze some measures of accessibility—defined by travel times to cities, transport infrastructure, and facilities at the sub-municipal level—using grid cells of five-by-five kilometers for the whole Italian territory and combining geocoded information with data from the national census and governmental offices. The measures computed in this paper offer a finer-grained quantification of accessibility, capturing differences within the same administrative level. Additionally, the grid cell approach—an analytical framework independent of political or administrative boundaries—allows for a more exogenous accessibility measurement. We use maps to visually present our findings.