Moreover, underneath the main settlements were dug extensive passageways. Notably, underneath the village at Chiunglin was formed a unique network of passageways. All residents, whether male or female, young or old, had to undergo mobilization, organization and training by civil defense authorities. The community center was later turned into an operations center, and throughout the village were set up 12 emergency entrances to form an effective defensive network.
而主要的聚落地底下都挖鑿了四通八達的坑道，尤其以「瓊林聚落」的戰鬥村地下網絡最為獨特，當時全村不分男女老幼，都需要接受民防部隊的動員、編組、操練，後來更以村辦公室為指揮中心，並在全村設立了 12 個緊急出入口，成為有效的防禦網。