What air raid shelters were used in world war 1?
There was no need for air raid shelters in the UK until World War 2. Air raid shelters weren’t built or used in the UK until World War 2 since World War 1 didn’t involve air assaults on Britain (aviation developed tremendously for military use and otherwise in the period between the two world wars). World War 1 was fought on various fronts in Europe (Western Front – trench warfare in France etc, Eastern Front etc).