The Huskar Pit's entrance still exists in Silkstone, Yorkshire, now covered by a memorial to the 26 children who died there. This specific shaft, barely four feet wide, was where children as young as seven descended daily into absolute darkness, and where they drowned when rain flooded the poorly maintained entrance. The Yorkshire coalfields stretched for miles underground beneath peaceful farmland, invisible cities where children hauled coal in tunnels too low for adults. Visitors to Silkstone today see green hills and stone churches.
Photo found at https://www.bbc.com/news/uk-england-south-yorkshire-44757270