---
title: "Africa's Stonehenge."
description: "Explore the controversial claims surrounding Adam's Calendar in South Africa—an alleged 250,000-year-old stone calendar that some call the oldest man-made structure on Earth, while skeptics see natural rocks and wishful thinking."
url: https://decodingtheunknown.pub/article/africas-stonehenge-adams-calendar.md
canonical: https://decodingtheunknown.pub/article/africas-stonehenge-adams-calendar
datePublished: 2026-06-28
dateModified: 2026-06-28
author:
  - name: Simon Whistler
    url: https://decodingtheunknown.pub/author/simon-whistler
publisher: Decoding the Unknown
image: "https://media.decodingtheunknown.pub/cdn-cgi/image/width=1600,height=900,fit=cover,quality=80,format=auto/articles/Lo4Lws1PZC8/hero.jpg"
type: Article
contentHash: 523e170236fe5640aa067a6a4d8e9448b70c59463ceebaeb40432274cd0bb06f
tokens: 58
summaryUrl: https://decodingtheunknown.pub/article/africas-stonehenge-adams-calendar.md.summary.md
---

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Explore the controversial claims surrounding Adam's Calendar in South Africa—an alleged 250,000-year-old stone calendar that some call the oldest man-made structure on Earth, while skeptics see natural rocks and wishful thinking.
<!-- aeo:section end="lede" -->