Saturday's breakthrough was a crucial milestone in a long and torturous effort that has captivated Chile and riveted the world.

It was a moment of euphoria. At 8:05 a.m. on Saturday, more than two agonising months after a mine collapse trapped 33 men nearly half-a-mile beneath the earth, a powerful drill fitted with pneumatic hammers pulverised the last feet of volcanic rock and struck air.

In the chilly desert above, machine operators yelped and poured Champagne. Bleary-eyed family members, who had gathered at the site through the night, waved the Chilean flag, sang the national anthem and shouted “Viva Chilean miners!”

Below, the miners erupted in cheers, their cries transmitted by radio to the surface. They had been trapped for 66 days, the longest known time that miners have survived a collapse. On the other side of the drill tip was their escape shaft to the surface.

“There have been hard moments, beautiful moments, sad moments, moments filled with happiness, nights where we were cold here,” said Juan Sanchez, 48, the father of Jimmy Sanchez, the youngest of the trapped miners. “But we just kept going, trusting in God that this would all work out. Right now, all I feel is happiness; it's like a calm has come over us.”

The breakthrough was a crucial milestone in a long and torturous effort that has captivated Chile and riveted the world. An extraordinary array of international talent had been gathered and new rescue techniques pioneered on the fly to plow through rock without compromising the miners' safety. Chilean officials brought in advisers from NASA, custom-built a steel rescue capsule and even fed the trapped miners meat pies baked in the form of cylinders to be slipped down a narrow hole more than 2,050 feet below the surface.

But the ordeal is far from over and officials said it was likely to be Wednesday at the earliest before the miners catch their first glimpse of sunlight and breath of fresh air. The words of Mining Minister Laurence Golborne tamped down the festivities. “The families are clear, the miners are clear what still needs to be done and the time it will take,” he said. “We still haven't rescued anyone.”

The next phase of the rescue effort is expected to be just as perilous. The rescue shaft is little more than two feet wide, and engineers have decided to line its upper walls with steel pipes to prevent rocks from tumbling into the shaft and blocking the way.

But installing tonnes of steel pipes is not without risk, and could even cause further collapse. The men will be raised one by one in the capsules, nicknamed the Phoenix, which engineers are concerned could snag the walls of the shaft. The miners themselves, some weakened by the ordeal, might have to set off dynamite to widen the hole on their end so that the capsule has enough room.

Even so, it is going to be a tight fit. The rescue shaft is not straight, bending through rocky walls and providing as little as a few inches of clearance around the capsule. The miners have been keeping their weight under control so they can fit in the capsule, which is about 21 inches wide and built with suggestions from the NASA team.

Atop the rescue drill, operators of the T-130, which beat out two other rigs working simultaneously to reach the miners, celebrated by pumping their fists in the air and spraying each other with Champagne. “This is a symbolic moment,” said Ximena Matas, a local city councilwoman. “The families have been waiting a long time for this.”

The gold and copper mine, near the northern city of Copiapo, caved in on August 5 but it was not until 17 days later that a small bore hole reached the miners and they sent up a message telling rescuers they were still alive.

All along, Chilean officials have worked to involve the miners in their own rescue, duties intended to aid the work as well as the miners' psychological health. Their work continued on Saturday as they helped the drillers bore through the final few feet, said Claudio Soto, an employee of Schramm, the maker of the T-130 drilling rig.

Mr. Soto said the miners were in radio contact with the chief driller, telling him when the tip of the drill first appeared. That way the driller could slow the machinery down, to avoid a sudden breakthrough of the entire drill, which would have put undue strain on the equipment.

“They were telling us how much more we had to go,” he said. “In that way it was a very, very controlled operation.”

Mr. Soto described the final few days of drilling as very intense, with the drill getting stuck several times. “The rock fought us back all the time,” he said. “It was really difficult. There had to be very precise work from the drillers.” The drill had to be removed from the hole twice, a process that took about 12 hours each time. He said the last moments before the breakthrough were very tense. “The whole crew was standing and looking at the drill pipe,” he said. “When we hit total depth, everybody was jumping and screaming and hugging each other … We opened some bottles of Champagne — not for drinking, just to celebrate.”

Workers spent much of the day removing bars and evaluating the integrity of the rescue hole by lowering in a video camera. Mr. Soto said there were noticeable fractures in the walls from the surface down to about 98 feet.

Many family members had said they preferred to wait a few days more to allow workers to case the hole than to risk the well-being of the miners.

At a news conference on Saturday night, Golborne, the mining minister, said officials had decided to install a steel liner along the top 315 feet of the shaft. The work was scheduled to start late Saturday.

More than 20 private companies worked on digging the three rescue holes, which were drilled simultaneously. In the end, the T-130 rig pounded through first. It used a special “downhole hammer” drill, made by Center Rock, a company in western Pennsylvania, that contains pneumatic hammers that pound the hard rock to bits as the drill rotates. “The downhole hammer technology was very, very helpful to develop a good penetration rate and break such a hard rock,” Mr. Soto said.

Later on Saturday, family members cheered and hugged operators of the rig as it was driven out of the mine with truck horns blaring.

The miners will be extracted one at a time, with two capsules alternating voyages. Each capsule contains tanks of oxygen-enriched air, a hands-free phone and retractable rollers to protect it as it bounces along the wall.

It remains to be decided in what order they will emerge, although officials said on Friday that the strongest would likely come out first, partly so they could help guide the rescue effort at the top, advising the emergency crews on conditions below. But officials also want the fittest on the first trips in case the capsule gets stuck and needs to be physically dislodged. Once the rescue capsules start running, the ordeal of more than 60 days will end with a one-way trip of 11 to 12 minutes, officials said.

(Alexei Barrionuevo reported from the San Jose Mine, and Christine Hauser reported from New York. Henry Fountain contributed from New York, and Pascale Bonnefoy from Santiago, Chile.) — New York Times News Service

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