Cook started his adventure last April at Africa's most southerly point, the South African village of L'Agulhas, and proceeded up the continent's west coast, running a total of over 16,000 kilometres.
"The first person ever to run the entire length of Africa. Mission complete," Cook posted on social media platform X.
Cook passed through Namibia, Angola, Democratic Republic of the Congo, Republic of Congo, Cameroon, Nigeria, Benin, Togo, Ghana, Ivory Coast, Guinea, Senegal, Mauritania and Algeria, before arriving at Ras Angela on Sunday evening.
The endurance athlete, who calls himself the "Hardest Geezer", has also raised more than half a millions pounds for charity along the way.
"The main goal is to challenge yourself and do something incredible which is what 'Hardest Geezer' is all about," Simon Klima of Givestar charity platform told Reuters.
"Simultaneously raise a lot of money for some really important causes, that's happening on the Givestar platform, so we are very privileged to have that happening there.
"So far nearly 600,000 pounds ($758,160.00) has been raised for two charities, Sandblast and the Running charity. Hopefully, going to hit a million pounds, Russ will hit a million pounds with his fundraiser, that's the target."
Cook was accompanied by supporters on the final leg of his journey, many of whom had flown out especially to be there.
"I saw the post on Instagram where he invited everyone out. I was laying on my couch, it was a Sunday afternoon, I saw it and he said everybody can come," Warren Blake from the U.S. told Reuters.
"I just couldn't miss a crazy historic opportunity like this."
Cook, wearing an England football jersey, arrived at the finish to chants of "Geezer, geezer", telling reporters: "I'm pretty tired", before enjoying a well-earned strawberry daiquiri.
