It is able to store 1,500 megawatt-hours of energy by compressing air into a massive abandoned underground salt mine in ...

But extracting the coveted salt means descending into dark caves, then blasting and carrying heavy rock. Faizan Panjwani: The problem is the massive size of the blocks that come from the mine.

The Wieliczka Salt Mine near Krakow is a marvel of human ingenuity and natural beauty, offering visitors a journey into an underground world of lakes, chapels, and chandeliers-all made of salt.