Throughout the ‘Cold War’, American military aircraft took off from Soesterberg airbase every day, their jet engines roaring. Local residents were not unduly perturbed by the noise; they referred to it as ‘the sound of freedom’. On Saturday 21 September, the Treaty of Utrecht Foundation will conclude its tercentenary celebrations with its own Sounds of Freedom. The roar of the jets makes way for the more harmonious offerings of local musicians, a display by serving members of the Dutch armed forces and a grand concert on the airbase runway.