Country fans can mark their calendars for April 15-17, 2016, when Blake Shelton, Tim McGraw and Dierks Bentley will all headline Fort Lauderdale's beachside Tortuga Music Festival, hosted by Rock the Ocean.

The concert, which will feature an additional third day for the first time this year, not only brings together a host of country’s biggest stars, but also raises awareness and funding for marine and ocean research, as well as conservation efforts.

The lineup will also include Sam Hunt, Cam, Thomas Rhett, Billy Currington, Kip Moore, Lynyrd Skynyrd, A Thousand Horses, Randy Houser, Chris Janson, Old Dominion and many more. The 2015 festival sold out, bringing more than 75,000 people to Fort Lauderdale Beach Park. Tickets are available on the event site.

The Tortuga Music Festival has contributed more than $250,000 toward ocean research and conservation since its inception. Rock the Ocean’s Conversation Village will also be on site, which will host more than a dozen organizations dedicated to the cause. The festival seeks to raise awareness about issues impacting the world’s oceans and support research and the conservation of marine life, particularly the sea turtles that nest annually along Florida’s Atlantic seaboard. For more information about the Tortuga Music Festival, visit the event website.

Shelton will also headline at next year's Country Jam festival in Grand Junction, Colo., while McGraw is slated to headline at We Fest 2016, which takes place in Detroit Lakes, Minn. from Aug. 4-6, 2016. For more information on the hottest festivals of 2016, check out our handy 2016 festival guide.

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