Tennessee may be small in size with a population of just over 7 million, but it is a heavy-hitter when it comes to its influence on popular music and American culture in the 20th century. The capital, Nashville, is the heart of country music performance and production, with its long- running Grand Ole Opry, Country Music Hall of Fame and the legendary stretch of honky-tonks and dance halls known as the District. Tennessee's many historical and contemporary attractions include: Great Smoky Mountains National Park, containing some of the highest mountains in eastern North America, is the most-visited national park in the United States. The Appalachian Trail, this world-famous hiking trail, spanning almost 2,200 miles, passes through Tennessee and attracts more than 3 million hikers each year. The Hermitage, President Andrew Jackson's 1,120-acre plantation, is now a museum that features exhibits covering all aspects of plantation life. Shiloh National Military Park, commemorating the battlefield of Shiloh, the Shiloh National Cemetery and other historical landmarks. The Titanic Museum, a two-story museum shaped like the Titanic, located in Pigeon Forge.