Dating back to the 13th century, this UNESCO World Heritage Site is as ... By the 13th century, the mine became the country's largest salt source, solidifying its importance.

American Rock Salt based in Livingston County is the largest salt mine in the country but has reported a shortage of its product, impacting some commercial plowing and salting companies in the area.

Road grit is actually the “remains of an ancient ocean” writes journalist Ed Conway, author of Material World ... while this might be the country’s largest salt mining operation, it does ...