Navy combat veteran Chris Ring says some people call him crazy for attempting to become the first American to swim the length of the Mississippi River.
But the 28-year-old Navy SEAL who served in Iraq and Afghanistan contends the extreme endeavor is worthwhile if it helps keep alive the memories of the country's fallen service members and the sacrifices of their families.
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"We all have what we have today because of these families and their loved ones," Ring said last week after finishing up a day's swim just south of Vicksburg, Mississippi.
See photos of his incredible journey:
Ring said he pitched the idea of the swim to the Legacies Alive nonprofit organization after learning many Americans were unaware of what it meant to be a Gold Star family, the designation given to those whose loved ones were killed in combat.
He began the journey, which Legacies Alive said will cover 2,552 miles, at Lake Itasca in Minnesota on June 6, the anniversary of D-Day, when thousands of Allied soldiers were killed or wounded during the 1944 invasion in northern France that helped bring about the defeat of Nazi Germany.
Averaging 6.5 hours in the water and 14 miles a day, Ring aims to reach the 0-mile marker where the Mississippi River meets the Gulf of Mexico in early December.
Ring has visited along the way with hundreds of people who lost family members to war and has encouraged them to sign the kayaks used by the team accompanying him on the swim.
At a recent stop, Jenny Smith of Brandon, Mississippi added the name of her son, Marine Staff Sergeant Jason Rogers, to a boat. Rogers, 28, was killed by an improvised explosive device while on patrol in Afghanistan in 2011.
Smith said she was encouraged by Ring's effort, noting she fears that families like hers will be forgotten.
"To be a part of a Gold Star family is something you don't ever want to be a part of but you're so proud, too, because you're part of a group of people who understand and support you," Smith said.
Rough weather has delayed Ring's swim a few times. But otherwise he has pushed through sickness, exhaustion and a shoulder injury, said Nicole Parke, spokeswoman for Legacies Alive, which is funding Ring's challenge and also raises money to erect memorials to fallen service members in their hometowns.
"To him, that sacrifice is nothing compared to what these families have gone through," she said.
(Editing by Colleen Jenkins and Bill Trott)
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