Chichen Itza: How the Maya Encoded 365 Days into Stone — and Built a Shadow-Serpent That Appears Twice a Year

Around 800 CE, Maya and Toltec builders raised El Castillo — a pyramid with exactly 365 steps, aligned so precisely that every spring and autumn equinox a shadow-serpent slithers down the staircase. Inside, they buried another pyramid with a red jaguar throne — all carved with stone tools, no metal, no wheels.

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