They are an unmissable, brutal piece of the Channel Island's landscape, but for some they are a window into our history.
While it is normally the time of year when we reflect on the end of the Occupation, the signs of the war remain a permanent fixture on our islands.
Like many aspects of Liberation 75, Festung Guernsey has had to change its plans to celebrate the anniversary of the end of the Occupation.
Volunteers interested in the dark history have worked to bring light to these hidden fortifications. Credit: ITV ChannelBattery Mirus was constructed from November 1941 and through the first half of 1942. Credit: Festung Guernsey Archive
The volunteer group manages 10 sites around the island and have been slowly returning to their restoration work while minding social distancing.
And interest in the old German bunkers is growing as the living memory of the Occupation slowly disappears.
Battery Mirus was the largest in The Channel Islands. Credit: Festung Guernsey Archive
