Mark Baumer was doing his part to raise awareness of climate change when he was struck and killed by a car on Saturday.
Baumer, 33, of Providence, R.I., was on day 101 of his cross-country walk when struck near Mossy Head, Florida. He was walking along the shoulder of the road when he was hit and died at the scene, USA Today reported.
Police said alcohol was not involved. Charges are pending against the driver.
I am running across America barefoot in order to save earth from dying from climate change.
Baumer's walk began in Providence in October and took him to Ohio before winter weather stalled his progress. He took a bus to Florida to continue his journey in warmer weather.
Baumer documented the 100th and final day of his journey.
Baumer's crowdfunding page, "Crossing America Barefoot to Save Earth from Climate Change," has raised more than $20,000.
He had trekked across America before. In 2010, he walked -- with his shoes on -- from the East Coast to the West Coast in 81 days.
Many took to Twitter to offer condolences.
Baumer documented his travels on Instagram.