Evacuation
noun, verbal noun
You’re looking for a neglected place that you can open up and use for evacuation.
While 避難 is a more general term for evacuating or seeking shelter during emergencies, 疎開 describes evacuating specifically from cities or crowded areas to safer places during disasters like earthquakes, tsunamis, etc.
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
空襲を避けるために田舎へ疎開していました。
They were evacuated to the countryside to avoid the air raids.