Wild boar protection sign, Sierra Alhamilla mountains around village of Nijar, Almeria, Andalusia, Spain, Europe

Electric fence, Auschwitz concentration camp, UNESCO World Heritage Site, Oswiecim near Krakow (Cracow), Poland, Europe

Gardiner Windmill, East Hampton, The Hamptons, Long Island, New York State, United States of America, North America

Electric car charging point and car parking space, Glasgow, Scotland, United Kingdom, Europe

Electric fence, Auschwitz concentration camp, now a memorial and museum, UNESCO World Heritage Site, Oswiecim near Krakow (Cracow), Poland, Europe

Electric fence, Auschwitz concentration camp, now a memorial and museum, UNESCO World Heritage Site, Oswiecim near Krakow (Cracow), Poland, Europe

Electric Fence at Mauthausen, Austria, Europe

Electric fence, Auschwitz concentration camp, now a memorial and museum, UNESCO World Heritage Site, Oswiecim near Krakow (Cracow), Poland, Europe

Electrified barbed-wire fencing and buildings at the museum of the former Auschwitz II-Birkenau concentration camp, UNESCO World Heritage Site, Poland, Europe

A flock of sheepby the Refuge Bertone, above Courmayeur, Italy.

Electrified barbed-wire fencing and buildings at the museum of the former Auschwitz I-Birkenau concentration camp, UNESCO World Heritage Site, Poland, Europe

Ratcliffe on Soar coal fired power station, protected by an electric fence and CCTV, near Nottingham, Nottinghamshire, England, United Kingdom, Europe

A free range pig and power station in Nottinghamshire, England, United Kingdom, Europe

Gas storage depot in Barrow in Furness, Cumbria, England, United Kingdom, Europe

Lighthouse near Albany, Western Australia, Australia

Electric fence of Rhino Sanctuary on red dirt road, tamarind (Tamarindus indica) with weaver birds (Ploceidae) nests in back, Tsavo West National Park, Taita-Taveta County, Kenya, Africa

Electrified barbed wire and trenches on the camp grounds, Dachau Concentration Camp, Dachau, near Munich, Bavaria, Germany, Europe

Electrified barbed wire, Dachau Concentration Camp, Dachau, near Munich, Bavaria, Germany, Europe

Tenting with electric bear fence, Tay Bay, Bylot Island, Sirmilik National Park, Nunavut, Canada