sentences:  Czechoslovak border fortifications
  
  Czechoslovakia built a system of border fortifications as well as some fortified defensive lines inland, from 1935 to 1938 as a defensive countermeasure against the rising threat of Nazi Germany.The objective of the fortifications was to prevent the taking of key areas by an enemy—not only Germany but also Hungary and Poland—by means of a sudden attack before the mobilization of the Czechoslovak Army could be completed, and to enable effective defense until allies—Britain and France, and possibly the Soviet Union—could help.