The Carnac stones of Brittany, France, comprise the largest concentration of megalithic monuments in the world — over 3,000 standing stones arranged in parallel rows across three primary alignments (Menec, Kermario, and Kerlescan), with associated tumuli, cromlechs, dolmens, and isolated menhirs. Erected between approximately 4500 and 2000 BCE over a span of 2,500 years, the Carnac complex spans the Neolithic and Early Bronze Age periods. Despite extensive archaeological investigation since the 19th century, the purpose of the alignments remains unknown. This paper presents the first comprehensive acoustic analysis of the Carnac complex, demonstrating that 24 of 28 measured structural dimensions (85.7%) encode the frequency F#6 (1,479.97 Hz) through standing wave harmonic resonance at less than 1.0% deviation. Fourteen dimensions achieve simultaneous dual-frequency encoding of both F#6 and D#2 (77.78 Hz) under 1.0% deviation. Critically, all three primary alignments — Menec, Kermario, and Kerlescan — independently encode F#6 and D#2 at sub-0.01% precision in their total lengths, demonstrating that the frequency pair was maintained across 2,500 years of construction by successive generations. This paper formally introduces Rios Harmonic Law: the proposition that ancient monumental structures across independent civilizations were intentionally dimensioned to encode the frequency pair F#6 and D#2 through standing wave harmonic resonance, representing universal acoustic constants independently recognized by human societies. With 9+ sites across six civilizations spanning from 3500 BCE to 1400 CE, the evidence base is now sufficient to elevate this pattern from hypothesis to a formally stated empirical law.
Abelardo Rios Jr (Mon,) studied this question.