For one veteran, honoring the fallen means pushing himself to his physical limit and accomplishing something few would even dream of attempting.

Chris Ring, a 10-year Navy combat veteran, is swimming down the entire length of the Mississippi River. To put this challenge in perspective, that’s swimming 2,552-miles nonstop with an average of 16 miles per day. If he accomplishes this feat, Ring will become the first American to ever swim through North America’s longest river from beginning to end.

Swimming more than 2,500 miles can’t be accomplished in a week, or even in a month. He started his great trek on June 6. He lost 20 pounds in three weeks, but Ring’s test of endurance has only just begun. The veteran is expected to hit the Gulf of Mexico on Nov. 11–just in time for Veterans Day.

Ring is swimming on behalf of Legacies Alive, a nonprofit devoted to supporting the families of servicemen who died during the war on the terror.