The three-day festival starts Friday.
There will be seven stages with 100 performers. All of it free. Headliners include the Indigo Girls, Los Lobos and Emmylou Harris.
More than 750,000 people are expected.
Fest300 - Why Hardly Strictly Bluegrass Is the Best Free Festival in America https://t.co/3JU3s1YXAd #fest300 #HSB15
— Hardly Strictly (@HSBFest) October 1, 2015