Border
Borders are generally defined as geographical boundaries, imposed either by features such as oceans and terrain, or by political entities such as governments, sovereign states, federated states, and other subnational entities. Political borders can be established through warfare, colonization, or mutual agreements between the political entities that reside in those areas. Some borders—such as most states' internal administrative borders, or inter-state borders within the Schengen Area—are open and completely unguarded.
Extends: Borders