(Reuters) - Rescue workers will start to evacuate Chile’s 33 trapped miners on Tuesday night and have started testing specially designed escape capsules to end their two-month ordeal, the government said on Monday.

Here is a timeline of the ordeal, one of the greatest mining accidents in Chile’s history.

August 5 - A cave-in leaves 33 miners trapped 2,300 feet vertically underground in a small copper-and-gold mine near the northern Chilean city of Copiapo, 500 miles north of Santiago.

The mine’s owners, local private company Compania Minera San Esteban Primera, notifies authorities several hours later, saying they first had to evaluate the situation.

August 6 - Mining Minister Laurence Golborne cuts short a visit to Ecuador and flies back to Chile to lead the rescue effort in Copiapo. Mine authorities pin their hopes on the possibility the trapped miners have reached a shelter where oxygen, water and food had been stored.

August 7 - Rescue workers, who began descending toward the shelter via a ventilation shaft on August 6, are forced to abandon that route when a fresh cave-in blocks the duct.

President Sebastian Pinera cuts short his visit to Colombia and returns to Chile to be with family members of the trapped miners at a temporary camp set up outside the mine.

August 8 - Rescue workers begin drilling bore-holes 5 inches in diameter into the mine to try to locate the miners.

August 11 - Pinera sacks the head of national mining regulator Sernageomin, and vows a major overhaul of the body, which monitors mine safety.

August 19 - The farthest-along drill reaches the level in the mine where authorities presumed the miners to be, but does not hit the shelter or encounter any signs of the miners.

August 22 - Early in the day, a drill reaches a depth of 2,260 feet and rescue workers hear tapping on the drill. Early in the afternoon, Pinera announces the miners had tied a note to the drill that said: “The 33 of us in the shelter are well.”

Hours later, rescue workers capture the first video images of the miners, showing them to be in much better condition than expected.

Golborne and Andre Sougarret, head of the rescue drilling operation, say rescue of the miners will take 3-4 months, given the instability of the mine and the time needed to drill a new hole, about 2 feet in diameter, to extract them.

August 23 - Food, water and medicine are lowered to the miners, who were running low on supplies found in the rescue chamber.

September 17 - A rescue drill reaches the miners. The small hole is widened over the next month to prepare for their evacuation.

October 4 - Golborne says the miners could be rescued in the second half of October. The men have started to prepare for their trip home by sending back to the surface gifts like soccer jerseys signed by Pele and rosaries blessed by the Pope.

October 8 - Golborne says a rescue shaft could reach the miners as early as that day and evacuation of the miners could begin the next week.

October 9 - Rescue workers finish drilling escape shaft, triggering jubilant celebrations, and the government says the men will be evacuated within days.

October 11- Rescue workers finish reinforcing the escape shaft with metal tubes to avoid any last-minute disaster, and the government says it will start to raise the men to the surface on Tuesday night.