A Pasadena Police Department reserve officer started day three of an expected six-month ride on horseback across the country Thursday morning at Pasadena’s Elks Lodge.

Colt Romberger, a reserve officer since 2012, decided to make the trek to the Vietnam War Memorial in Washington, D.C., in honor of his father, a Vietnam veteran who died in 2015 from a brain disease tied to exposure to Agent Orange, a chemical weapon used by U.S. military forces during the war.

“These guys are dying from something that happened to them 40 years ago,” Romberger said. “We’re trying to do this so that the nation as a whole can finally welcome these guys home.”

Agent Orange was a herbicide used by the U.S. military during the Vietnam War. Decades later, the herbicide has been connected to health issues experienced by soldiers exposed to the chemical.

Through the nonprofit Expedition Orange, Romberger hopes to raise awareness about the chemical, not just with the general public, but with veterans who may not realize the effects the exposure could have on them. The 3,000-mile journey began on Sunset Boulevard in Los Angeles with a police escort guiding Romberger and his horse through the city streets.

On Thursday, an escort led Romberger through the streets of Pasadena, beginning at the Elks Lodge on Colorado Boulevard. Police departments throughout the region have “been stellar” in helping Romberger, an Air Force veteran, get through their communities without issue, he said.

A family friend is following along on the journey with a trailer and portable stable for the horse. Romberger also has additional horses to switch to as needed if his current horse begins to show signs of exhaustion or becomes injured.

Though the journey is slow, Romberger, who grew up on a horse ranch, said breaks are scheduled throughout the trip to ensure the horses stay healthy. The goal is to travel about 15 to 20 miles per day. The trip was planned over the last two years.

Donations to the group will help fund the trip and raise awareness, but Romberger is hoping the publicity will allow the group to expand Expedition Orange to help fulfill the wishes of veterans affected by Agent Orange. The group raised about $10,000 through a GoFundMe campaign.

“We want to give you a proper thank-you and a welcome home,” Romberger said, describing it as a sort of “Make-A-Wish” for veterans. “If you always wanted to go see an NFL football game, we want to get you a ticket.”