The Great Circle

Quantifying ancient monument alignment across eight independent databases

Overview

The Great Circle program examines a long-discussed but never rigorously tested observation: that a disproportionate number of ancient monuments fall near a single great circle path first identified by Jim Alison. Using 550,000+ sites from 8 independent archaeological databases, the program applies statistical methods with land-constrained Monte Carlo baselines to distinguish genuine clustering from geographic coincidence.

Key Findings

1. Monument Enrichment: 2.52×

Monuments within 200 km of the Alison circle occur at 2.52 times the rate expected under a land-constrained null model (Z = 6.74). This is not an artefact of database selection — the enrichment replicates across all 8 databases.

2. Settlement Anti-Clustering: Z = −2.91

Non-monumental settlements show the opposite pattern: they are significantly under-represented near the circle. The divergence between monument and settlement distributions is the key finding — it cannot be explained by geographic sampling bias.

3. Temporal Concentration

The enrichment peaks between 3000–2000 BCE, driven entirely by Egyptian Old Kingdom pyramids in the Memphis Necropolis (within 7 km of the circle). This temporal specificity is inconsistent with a uniform geographic explanation.

4. Civilisation Collinearity

Four independently originated civilizations (Egypt, Indus Valley, Persia, Easter Island/Nazca) fall within 200 km of the circle. Monte Carlo testing estimates p = 0.00042 for this degree of collinearity under random placement.

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Papers & Data

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