Description: Aerial photo of Fort Opau, 24 April 1954

Reference: Survey SN847, Run 2389, Photo 3. Sourced from http://retrolens.nz and licensed by LINZ

Copyright status: CC-BY 3.0

Description: Aerial photo of Fort Opau, 1 November 1966

Reference: Survey SN1407, Run 3295, Photo 23. Sourced from http://retrolens.nz and licensed By LINZ

Copyright status: CC-BY 3.0

Description: Aerial photo of Fort Opau, 28 September 1969

Reference: Survey SN3185, Run 4231, Photo 3. Sourced from http://retrolens.nz and licensed By LINZ

Copyright status: CC-BY 3.0

Description: Aerial photo of Fort Opau, 21 January 1974

Reference: Survey SN3672, Run 4736, Photo 20. Sourced from http://retrolens.nz and licensed by LINZ

Copyright status: CC-BY 3.0

Description: Aerial photo of Fort Opau, 20 November 1974

Reference: Survey SN3773, Run C, Photo 7. Sourced from http://retrolens.nz and licensed By LINZ

Copyright status: CC-BY 3.0

Description: Aerial photo of Fort Opau, 9 September 1980

Reference: Survey SN5497, Run B, Photo 3. Sourced from http://retrolens.nz and licensed By LINZ

Copyright status: CC-BY 3.0

Description: Aerial photo of Fort Opau, 21 December 1987

Reference: Survey SN8790, Run U, Photo 6. Sourced from http://retrolens.nz and licensed by LINZ

Copyright status: CC-BY 3.0