London, Jan. 16: The world record for the longest echo has been broken by a hidden network of oil storage tanks in Rossshire.
Scientists came out of the Inchindown oil storage tanks, an underground fuel depot built during WWII, with evidence that gun-shot fired inside the tunnel resonates for a full 112 seconds, the Independent reported.
The previous record holder was the Hamilton Mausoleum, also in Scotland, where the sound of the doors being slammed shut took 15 seconds to die.
Guinness World Records has certified the findings made by Trevor Cox, Professor of Acoustic Engineering at the University of Salford.
The tanks, excavated out of solid rock between 1939 and 1941, were dug deep into the hillside amid concerns about the strengthening of Germany's armed forces.
The tunnels were built to provide a huge bomb-proof reserve supply of furnace oil for the warships of the home fleet at Invergordon, a key Royal Navy anchorage; it was designed to hold 25.5 million litres of fuel and has walls 45 cm thick.
The tank is about twice the length of a football pitch, 9m wide and 13.5 metres high. (ANI)