A ring of sinkholes in Mexico traces the crater that killed the dinosaurs

The Chicxulub asteroid impact 66 million years ago left a crater roughly 180km wide, long since buried under Yucatán limestone. Groundwater deflected around its hidden rim has dissolved a near-perfect semicircle of cenotes stretching coast to coast — an underground scar from the impact still traceable from the surface today.

— Eugene Perry et al., Ring of Cenotes (Sinkholes), Northwest Yucatan, Mexico — Geology, 1995