What on Earth? Season 11 Episode 4 - Mystery of the Welsh Mine

Airdate: 2022-Jul-13

Episode summary:

Satellite images capture monumental ruins surrounded by bizarre feather-shaped structures on a Welsh mountaintop; experts investigate a hidden tunnel containing the remains of an abandoned slate mine with an exploitative and deadly past.

About What on Earth? series:

What on Earth? is a documentary series using satellite images of strange geological occurrences and man-made structures on Earth to examine such ma...Show more >