Roxanne Wicke, Age T, Of Trenton, Neb., For her question;

Where are the world's largest salt mines?

A salt mint is a solid layer of salt which may reach half a mile under the ground. The salt crystals art packed tightly together in a hard mass  which is often grubby with grimy dirt. The biggest salt mine in Europe is in Austria. This buried layer of salt equals a huge square 30 miles long on each side. In Poland, there is a vast salt mint reaching down almost a quarter mile.

There is some salt buried almost everywhcre, but in most places the supply is not worth mining. Michigan, New York and Louisiana lead the United States in salt production, and our richest supplies art on avery island off Louisiana. Each year, we take about 18 million tons of salt from mints and more than four million tons from the sea.