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.

Quotes

• My father, whom the robber Afghans vex,
  And clip his borders short, and drive his herds,
  And he has none to guard his weak old age:
  There would I go, and hang my armour up,
  And with my great name fence that weak old man.
  • Matthew Arnold, Sohrab and Rustum (1853)

• BOUNDARY, n. In political geography, an imaginary line between two nations, separating the imaginary rights of one from the imaginary rights of the other.
  • Ambrose Bierce, The Devil's Dictionary (1911)

• Tom’s country ends here: he will not pass the borders.
  Tom has his house to mind, and Goldberry is waiting!
  • J. R. R. Tolkien, The Fellowship of the Ring (1954), "Fog on the Barrow-downs"