The 2014 Headwaters Country Jam has added Montgomery Gentry to its lineup.

The hard-rocking country duo, whose hits include 'Speed,' 'Hell Yeah,' 'Lucky Man' and 'Gone,' join previously-announced acts Dustin Lynch, Sammy Kershaw, Chase Rice and LoCash Cowboys at the festival, which takes place next June 26-28 in Montana.

Headwaters Country Jam has become the largest country music festival in Montana since it launched in 2008. The yearly event takes place at a 159-acre campground and music venue called the Bridge — the final resting place of the historic Sappington Bridge that once crossed the Jefferson River.

Over the years it has presented some of country’s biggest acts, including Eric Church, Lonestar, Luke Bryan and Eli Young Band.

2014's event features special packages with access to a VIP area near the stage, daily Happy Hour with free beer, access to bathrooms not open to the general public, opportunities at special merchandise and more.

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