Which is the smallest practical planning unit in regional planning?

In the context of regional planning, the county is considered the smallest practical planning unit due to its administrative and governance structure. Counties often encompass multiple cities, towns, and rural areas, providing a more comprehensive framework for planning and resource management.

Counties have defined geographical boundaries and are integral in coordinating services such as transportation, land use, public health, and environmental regulations across a larger area than a single city or village can manage. This capability allows for more significant integration of planning efforts and policies that address regional issues, such as infrastructure needs, economic development, and environmental protection.

In contrast, while the individual, village, and city represent smaller units, they typically do not have the same level of resources and authority to govern as effectively on a regional scale. Therefore, the county serves as a vital link in regional planning efforts, obtaining a balance between local needs and broader regional goals.