Final answer:
The interstate highways map showing major cities and routes in the southeastern United States relates most directly to externalities concerning land use, reflecting how transportation infrastructure affects regional development, urbanization, and the spatial distribution of economic and social activities.
Step-by-step explanation:
The data on an interstate highways map of the southeastern United States would most directly relate to land use externalities. The detail of the highways' networks and the major cities they connect indicates an analysis of the impact of transportation infrastructure on regional development, urbanization, and potential shifts in land use. This infrastructure facilitates economic activities by improving accessibility and mobility, thereby influencing patterns of land use both positively and negatively. For example, interstate highways are associated with urban sprawl, changes in local economies, and shifts in population densities.
The construction of the interstate highway system was designed to simplify commuting from suburbs to cities and had significant impacts on urban working-class neighborhoods, often leading to their destruction. It also shifted resources away from public transportation, affecting those without personal vehicles. Moreover, the highways bypassed small towns, often diminishing their economic vitality as traffic was redirected to more efficient routes.
In the broader context, highways have been critical in fostering urbanization and economic growth in regions like Atlanta, contributing to the South's upward mobility in the nation's economy. However, areas that have been bypassed or have not benefited directly from this infrastructure, such as parts of the rural South and Mississippi Delta, often remain impoverished. The strategic land use affected by the presence of interstates is thus a significant factor in regional development and is indicative of the varied socio-economic conditions across these states.