LAS GAVIOTAS, Colombia  In the 1960s, an aristocratic Colombian development specialist named Paolo Lugari took a road trip across these nearly uninhabited eastern plains, a region so remote and poor in soil quality that not even Colombia’s historic upheavals of violence had taken root here at the time.

Stopping to rest in this vast expanse, written off by agronomists as the equivalent of a tropical desert, Mr. Lugari decided it was the perfect place to experiment with the future of civilization. He founded a village unlike any other in this war-weary country.

“The only deserts that exist in this world are deserts of the imagination,” said Mr. Lugari, 64, on a visit this month to the community he named after the river gulls, or gaviotas, he saw flying overhead on that trip more than 40 years ago.

These days, visitors travel by propeller plane over the bleak savanna to get here, or by bus past the occasional guerrilla or paramilitary checkpoint. The visitors rarely come. But when they do, they get a glimpse into a four-decade experiment to alter civilization’s dependence on finite fossil fuels and industrial agriculture.