Pod Academy

It's official, the world's longest echo can be heard at an oil storage complex at Inchindown, near Invergordon in Scotland.  Hear it by hitting the play button above. The 1970 Guinness Book of Records holds the last claim for the longest echo. When the solid-bronze doors of the Hamilton Mausoleum in Scotland slammed shut, it took 15 seconds for the sound to die away to silence. The Inchindown echo is a full minute longer. Professor Trevor Cox of Salford University discovered the Inchdown echo while working with Allan Kilpatrick, an archaeological investigator for the Royal Commission on the Ancient and Historical Monuments of Scotland. Allan fired a pistol loaded with blanks about a third of the way into the storage tank, and Trevor recorded the response picked up by the microphones about a third of the way from the far end - a standard technique used in concert hall acoustics.  At 125 Hertz, a frequency typically made by a tuba, the reverberation time was 112 seconds. Even at the mid-frequencies important