№ 12Relic · Kent, England

The Denge Sound Mirrors

Three concrete ears on the Kent marshes, built to hear enemy aircraft before radar made them obsolete.

All three concrete sound mirrors at Denge, the long wall, the small dish and the great bowl, stand in rough scrub under a clear sky. — Pl. IThree ears against the sky

The thirty-foot concrete bowl of a Denge sound mirror tilts skyward above dry grass, its listening pole still in place. — Pl. IIBuilt to hear the bombers

The curved two-hundred-foot wall mirror at Denge recedes under heavy grey cloud, its concrete stained and streaked with age. — Pl. IIITwo hundred feet of listening

Photographs Julian P Guffogg (CC BY-SA 2.0) · Bodacea (CC BY-SA 2.0) · Wikimedia Commons

Before radar, Britain listened. On the shingle near Dungeness stand three vast concrete acoustic mirrors from the late 1920s — a 20-foot dish, a 30-foot bowl and a curving 200-foot wall — designed to focus the drone of approaching engines onto microphones, giving a few minutes' warning of raids across the Channel.

Radar arrived within a decade and the listening ears were abandoned mid-thought. They now stand marooned on an island in a flooded gravel pit, guarded by birds — brutalist sculpture by accident, and one of the strangest silhouettes in England.

Field notes

The knowledge

Getting there: At Lade, near Dungeness, Kent; the mirrors sit on an island in the RSPB gravel pits, viewable year-round from the public footpaths around the lakes.
Best time: Guided open days — run occasionally in summer — get you onto the island itself; otherwise a clear evening makes the silhouettes.
Local tip: Combine with Dungeness proper: Derek Jarman's garden, two lighthouses and the strangest landscape in the south-east.

Field position50.9560° N · 0.9540° E

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