Paul Prior has supplied an old photograph, possibly taken circa 1969-70, showing the sound mirror at Warden Point near Leysdown on the Isle of Sheppey.

The picture was taken before the cliffs were eroded so far that the mirror fell onto the beach below, which is thought to have happened in about 1978-79.

The mirror is on the extreme left of the picture. The design is similar to the mirrors at Selsey and in the northeast, suggesting a First World War date for its construction.