Scallywag bunkers or Auxiliary Unit Operational Base/OB were underground bunkers used by GHQ Auxiliary Units of the British Resistance against axis invasion of the United Kingdom.[1][2][3][4][5]
Background
Operational Patrols consisted of between four and eight men, often farmers or landowners. They were usually recruited from the most able members of the Home Guard, possessed excellent local knowledge and were able to live off the land. Gamekeepers and even poachers were particularly valued.[6] They were always intended to fight in Home Guard uniform and from 1942 the men were badged to Home Guard battalions 201 (Scotland), 202 (northern England), or 203 (southern England).[citation needed]
Each Patrol was a self-contained cell, expected to be self-sufficient and operationally autonomous in the case of invasion, generally operating within a 15-mile radius. They were provided with elaborately-concealed underground Operational Bases (OB),[7][8] usually built by the Royal Engineers in a local woodland, with a camouflaged entrance and emergency escape tunnel.[9] It is thought that 400 to 500 such OBs were constructed in England, Wales and Scotland.[9]