Philippine climate change envoy Naderev Sano will reach on Saturday ground zero of the strongest typhoon ever to make landfall, completing an epic march he believes will help spur action against global warming.

Sano will end his 1,000-kilometer trek in Tacloban, a major city in the central Philippines that was among the worst hit when Super Typhoon Haiyan struck exactly one year ago.

"It's been a wonderful journey. Physically, the walk is starting to take a toll ... but everyone is in high spirits, and so am I," Sano said as he reached the final rest-stop in the typhoon-damaged town of Basey.