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# Preserving the Concrete Listening Ears of Early Surveillance
- URL: https://hyperallergic.com/preserving-the-concrete-listening-ears-of-early-surveillance/
- Published: 2015-07-10T01:37:24.000Z
- Updated: 2025-11-24T15:59:24.000Z
- Description: Prior to the invention of radar in the 1930s, a system of concrete acoustic mirrors was set up around the coast of the United Kingdom as an early form of surveillance.
- Author: Allison Meier
- Tags: Art, Architectural Preservation, Preservation, Surveillance, World War I, #wp, #wp-post, #image-position-hidden, #Import 2025-11-24 07:08 (2014, 2015, part 2)

![The restored Fulwell Acoustic Mirror (© North News and Pictures)](https://storage.ghost.io/c/51/f8/51f871d8-b6be-4a73-b958-0ca4fff0110a/content/images/hyperallergic-newspack-s3-amazonaws-com/uploads/2015/07/fulwellmirror01.jpg)

The restored Fulwell Acoustic Mirror (© North News and Pictures)

Prior to the invention of radar [in the 1930s](https://en.wikipedia.org/wiki/History%5Fof%5Fradar?ref=hyperallergic.com), a [system](http://www.limestonelandscapes.info/Pages/ADefendedLand.aspx?ref=hyperallergic.com) of concrete [acoustic mirrors](https://en.wikipedia.org/wiki/Acoustic%5Fmirror?ref=hyperallergic.com) was set up around the coast of the United Kingdom as an early form of surveillance. These “Listening Ears” were constructed in response to ruinous German zeppelin raids during World War I. Due to neglect and obsolescence, most were [demolished](http://www.chroniclelive.co.uk/news/north-east-news/sunderland-first-world-war-zeppelin-9420976?ref=hyperallergic.com). One of England’s six preserved World War I mirrors was just restored in a $100,000 project [completed last month](http://www.historicengland.org.uk/news-and-features/news/first-world-war-acoustic-mirror-sunderland?ref=hyperallergic.com).

The Fulwell Acoustic Mirror at Fulwell, Sunderland, was cleaned and outfitted with a new heritage park in a collaboration between Historic England, Sunderland City Council, and the Heritage Lottery Fund’s Limestone Landscapes. Built in 1917 after a 1916 zeppelin bombing in the area [killed 22](http://www.culture24.org.uk/history-and-heritage/military-history/first-world-war/art528436-first-world-war-acoustic-mirror-built-to-warn-of-zeppelin-attacks-restored-in-sunderland?ref=hyperallergic.com), it was briefly operational and, [according to the Sunderland Echo](http://www.sunderlandecho.com/history-nostalgia/sunderland-s-world-war-one-listening-ear-officially-reopens-1-7300721?ref=hyperallergic.com), was used to plan a successful counterattack in 1917\. Decades of abandonment followed and the mirror was [hidden](http://www.sunderlandecho.com/history-nostalgia/wearside-echoes-sunderland-s-first-world-war-listening-ear-targeted-by-clean-up-video-1-4880975?ref=hyperallergic.com) by overgrown brambles and nettles. In 2011 the decay earned it a place on Historic England’s [Heritage at Risk list](http://Historic England Heritage at Risk).

![The Fulwell Mirror before restoration (© Historic England)](https://storage.ghost.io/c/51/f8/51f871d8-b6be-4a73-b958-0ca4fff0110a/content/images/hyperallergic-newspack-s3-amazonaws-com/uploads/2015/07/fulwellmirror02.jpg)

The Fulwell Mirror before restoration (© Historic England)

Acoustic mirrors work a bit like a satellite (or your own ears), concentrating sound at a point with the concave shape. When operational, a microphone was situated at this point, and someone would listen in with headphones, potentially giving a 15 minute warning for incoming zeppelins or sometimes water vessels. In 2014, [Tim Bruniges’s “Mirrors](https://hyperallergic.com/aural-mirrors-on-sounds-stage/)” installation at Signal Gallery in Brooklyn recreated this technology on a small scale with two concave mirrors on either side of a room, the ambient noise piped back into the space with two giant speakers.

As a mostly forgotten innovation in the development of surveillance, the acoustic mirrors are interesting to revisit, yet the Fulwell Acoustic Mirror is also a case study in preserving concrete heritage. As a porous material, concrete can become difficult to repair and corrodes if neglected (the acoustic mirror’s restoration included[ diluted sheep droppings](https://historicengland.org.uk/news-and-features/news/first-world-war-acoustic-mirror-sunderland/?ref=hyperallergic.com) as a cleaning solution).

Brutalist architecture in particular is experiencing this wear, such as the Orange County Government Center in Goshen, New York, which was closed in part due to [wear](http://www.preservationnation.org/magazine/2013/winter/defending-brutalism.html?referrer=https://www.google.com/&ref=hyperallergic.com#.VZ2FhMZVhHw) on its concrete. Its demolition [started earlier this month](http://blog.preservationnation.org/2015/07/06/in-transition-the-orange-county-government-center-goshen-new-york/?ref=hyperallergic.com#.VZru6%5FlVhHw). Currently Robin Hood Gardens in London with its concrete façade [is also in danger of demolition](http://www.archdaily.com/643565/richard-rogers-appeals-for-public-support-to-save-robin-hood-gardens-from-demolition?ref=hyperallergic.com). These are just a couple of examples of historic concrete structures[ in danger](http://www.citylab.com/design/2015/01/the-case-for-preserving-historic-concrete/384998/?ref=hyperallergic.com). The acoustic mirror is a much smaller scale project than a whole building, but it does highlight a material that will be central to much of 20th-century architectural preservation.

![Acoustic mirrors at Romney Marsh, England (photo by Tom Lee, via Flickr)](https://storage.ghost.io/c/51/f8/51f871d8-b6be-4a73-b958-0ca4fff0110a/content/images/hyperallergic-newspack-s3-amazonaws-com/uploads/2015/07/acousticmirror06.jpg)

Acoustic mirror at Romney Marsh, England (photo by Tom Lee, via Flickr)

![Acoustic Mirror](https://storage.ghost.io/c/51/f8/51f871d8-b6be-4a73-b958-0ca4fff0110a/content/images/hyperallergic-newspack-s3-amazonaws-com/uploads/2015/07/acousticmirror01.jpg)

Acoustic mirror in Kilnsea, England (photo by John Poyser, via geograph.org.uk)

![Acoustic Mirror](https://storage.ghost.io/c/51/f8/51f871d8-b6be-4a73-b958-0ca4fff0110a/content/images/hyperallergic-newspack-s3-amazonaws-com/uploads/2015/07/acousticmirror02.jpg)

A WWI British aviator and Zeppelin raider illustrated in “Canada’s sons and Great Britain in the world war” (1919) (via Internet Archive Book Images)

![Acoustic Mirror](https://storage.ghost.io/c/51/f8/51f871d8-b6be-4a73-b958-0ca4fff0110a/content/images/hyperallergic-newspack-s3-amazonaws-com/uploads/2015/07/acousticmirror03.jpg)

Damage from a 1915 zeppelin raid in England (via Girdwood Collection, British Library)

![Acoustic Mirror](https://storage.ghost.io/c/51/f8/51f871d8-b6be-4a73-b958-0ca4fff0110a/content/images/hyperallergic-newspack-s3-amazonaws-com/uploads/2015/07/acousticmirror04.jpg)

Acoustic mirror on the coast between Dover and Folkestone in England (photo by GanMed64, via Flickr)

[*Fulwell Acoustic Mirror*](http://www.sunderland.gov.uk/index.aspx?articleid=3242&ref=hyperallergic.com) *is on Namey Hill near the city of Sunderland, England.*