The couple have been working with charity A Drop In The Ocean to volunteer at the Nea Kavala relocation camp, which is 20 km away from the Macedonian border.
Camilla and Jamie shared photos from their experience volunteering at the site, offering refugees food and clothing.
Revealing their work is also being filmed for a short documentary, Camilla wrote on Instagram: “We were incredibly lucky today to have the opportunity to volunteer with A Drop in the Ocean (@drapenihavet) in Nea Kavala camp.
“This incredible organisation abides by true humanitarian principles, delivering essential food and clothing in a dignified manner under difficult circumstances. Our whole trip has been coordinated by the amazing @hollypenalver founder of @indigovolunteers, and after an exceptional day one we are so excited to see what the rest of the week will bring.
“We will be keeping you updated on a daily basis, and will provide full information on how you can get involved in a short documentary when we get back.”
Jamie added: “The best first day of our trip I could have imagined, I have never had such a rewarding experience.
“Looking forward to the rest of the week and many more trips to come!”
Shortly after leaving the ‘Love Island’ villa, Camilla, who works in humanitarian explosive ordnance disposal, revealed she planned to use her new-found fame for good.
She told HuffPost UK: “I want to use any platform I have to draw attention to any issues that are important to me.
“There’s a couple other places I’m thinking of going.”
Camilla also revealed she would “literally love” to make a Ross Kemp-style documentary about her work, adding: “Very interestingly, we actually mentioned that on our second date, as that was one of the things Jamie brought up as something he would like to do too.”