Discovered in the Middle East over 1500 years ago, Qataris used to attribute the sounds to evil Djinns. Explorers like Marco Polo shared tales of the low-pitched desert sounds over 700 years ago. The sand dunes actually make noises when you walk on them. The noise we're hearing is the sound of sand grains rubbing against each other. The quality of sound produced depends on the size and texture of the grains. The grains must all be similar in size, rounded, dry and free of other particles. When sand accumulates at the top of a dune, it eventually reaches a tipping point and slides down the other side of the dune in a sand avalanche. The face of the dune acts like a speaker, amplifying the sound of the grains colliding. As the sand passes over itself, it produces vibrations that result in sounds like a cello or didgeridoo. Researchers have measured the noise levels, and some booming dunes reach up to 110 decibels -- as loud as a snow blower or motorcycle! Located 40 km southwest of Doha, they are a rare natural phenomenon that we are so happy to have checked out on such a unique night. It is one of only 30 places on the pant where sound is naturally produced from the sand dune. The semi-circular dune formed a natural amphitheatre and they placed a huge camp fire right beside it. Pretty cool. There were hundreds of expat families there from all over the world. As we walked around, you could hear a number of different accents. People crawling like little ants all over the dune. They kids could not wait to climb up it and run or roll down. It is flat in all directions and then all of a sudden the dunes appear.
Source: howstuffworks.com
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