Kenai to Key West-- that's the mission for runner Pete Kostelnick.

Kostelnick kicked off his cross-country campaign with a light run up the Kenai Peninsula.

He estimates if he runs 50 miles a day, it will take about 100 days to run from Homer to Key West.

At night, Kostelnick is camping. By day, he's pushing a running stroller which carries all his gear.

The Iowa native wants to be the first person to travel from Alaska to Florida on foot-- a whopping 5400 miles.

"This run, it was kind of just my own imagination-- and to start here in Alaska, run along the Alaska Highway, a highway I rode with my family 19 years ago-- it's just a dream come true," Kostelnick said.

This isn't his first long run, either. Two years ago, Kostelnick ran from San Francisco to New York -- coast to coast -- in 42 days. It broke a world record.

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