The state of Ohio is bordered Michigan, Indiana, Kentucky, West Vifginia, Pennsylvania, and Lake Erie. It covers an area of 44,825 square miles and has a population of 11,466,917 as of 2007. Columbus is the state's capital and was named after the explorer Christopher Columbus. Columbus is also known as home to Ohio State University, the largest university in the United States. Industry includes education, insurance, healthcare, retail, and technology. Ohio is the top state in lime production and among the leaders in coal, clay, salt, sand, and gravel. Tourists also enjoy the many shops, sceenery, bed and breakfasts in the Old Amish country.