On November 14, 2001, a strong earthquake occurred on the high plateau of western China. At a distance of 1800 km from the epicenter, coherent infrasonic waves were detected for more than one hour. Using both an inverse location procedure and a complete simulation of the radiated pressure field, distant source regions are accurately located. The seismo-acoustic coupling along a mountain belt is clearly demonstrated. Such an event offers an opportunity to validate velocity models in the atmosphere as well as to improve the understanding of the amplification of ground displacement caused by the topography.