When the squat, red firetruck, smelling of greasy french fries, reached the literal end of the road, two young Americans jumped out and gave each other high fives.

Nine months after they set off from Alaska to spread the gospel of biofuels, Seth Warren and Tyler Bradt completed their journey on Sunday at the end of Highway 3, which dead-ends at the southern tip of South America.

Along the way, the twenty-something buddies made hundreds of stops on two continents to ask for people's used frying oil and animal fat, which powered their truck.