Georgia is a state located in the southeastern United States. From 2007 to 2008, 14 of Georgia's counties ranked among the nation's 100 fastest-growing, second only to Texas. Georgia is known as the Peach State and the Empire State of the South. Atlanta is the capital and the most populous city. Georgia is bordered on the south by Florida; on the east by the Atlantic Ocean and South Carolina; on the west by Alabama; and on the north by Tennessee and North Carolina. Each region has its own distinctive characteristics. For instance, the Ridge and Valley, which lies in the northwest corner of the state, includes limestone, sandstone, shale and other sedimentary rocks, which have yielded construction-grade limestone, barite, ocher and small amounts of coal. Georgia has a diverse mix of flora and fauna. The State has approximately 250 tree species and 58 protected plants and the majority of Georgia is primarily a humid subtropical climate. There are 63 parks in Georgia, 48 of which are state parks and 15 that are historic sites, and numerous state wildlife preserves.