MENE GRANDE, Venezuela — On a hill overlooking this heat-baked town, a small oil well painted in the national colors of yellow, blue and red gives off a constant whir as it bobs up and down.

Crude oil continues to flow through pipes here just as it did 100 years ago, when this became the country’s first successful oil well, setting Venezuela on the path from a sleepy backwater of coffee farmers and cattlemen to one of the world’s most petroleum-rich countries.

But today, just a short distance from this landmark oil well, known as Zumaque 1, the streets are unpaved and people live in shacks made from corrugated metal sheets. Even after a century of pumping, the oil is still so close to the surface that it seeps from the ground on its own, a sticky black reminder of wealth amid poverty.

“Look at the riches of Venezuela,” said Ramón Materán, 64, a laborer, gesturing toward the oozing crude oil that seeped from the ground in his neighborhood, called Baralt 1. Then, looking around the neighborhood, with its potholes and shacks with no sewer connections, he said, “For all of Venezuela’s riches, things are pretty neglected here.”