In 2006, Cyrus released the first "Hannah Montana" soundtrack album. It has sold 4.5 million copies. It reached number one on the US "Billboard" 200. In 2007, she released a double album, "Hannah Montana 2: Meet Miley Cyrus". The first CD was a soundtrack album for "Hannah Montana", and the second CD was Cyrus' first studio album. She starred in the Best of Both Worlds Tour.