The wrecked Costa Concordia liner has been successfully refloated off the coast of Giglio island, in preparation for its last cruise to Genoa where it will be dismantled.

The largest maritime salvage operation in history entered its final phase at first light on Monday, with salvage crews pumping compressed air and draining water from 30 watertight boxes, or sponsons, welded to the sides of the ship.

By midday, more than two years since the cruise liner capsized off the Tuscan island of Giglio killing 32 people, the 114,000-ton vessel was floating again. The ship was raised by nearly 13 feet at its stern and by 6.5 feet at its bow, dramatically changing her appearance. Haunting dark brown cabins, submerged since the disaster, became visible again.

Photos: See the Refloating of the Costa Concordia Step by Step

Engineers expressed satisfaction about the first day of the daunting operation. Raising the 950-foot-long and 115-foot-wide liner off the platform where it had been sitting since it was placed upright nine months ago was considered one of the most critical parts of the entire refloating project.

However, technicians still have a long way to go. The aim is to raise the liner by nearly 14 meters (45.9 feet). Sandwiched between the floating sponsons, the Concordia will then embark on a 170-mile journey at the slow speed of 2 knots.

"Refloating the liner so that it can depart from Giglio might take a week or, at best, five days," said Franco Porcellacchia, the director of technical operations at Concordia's owner, Costa Cruises.

The operation is being carried out by engineers of the U.S. Titan Salvage and Italian Micoperi companies. Some of them, including the salvage master, Nick Sloane, were directing the operations aboard the Concordia.

The Concordia: Recounting a Disaster: Photos

"It is a complex operation never attempted before, but we know we can count on the best technicians," Costa Cruises CEO Michael Thamm said.

He added that the cost of the project will amount at about 1.5 billion euros (about $2.3 billion).

About two-and-a-half times the size of the Titanic, the Concordia will now be towed 30 meters away from the shore and moored by a series of anchors and steel cables. Two tugs on the offshore side and a third at the Concordia bow will keep in place the massive ship.

On Tuesday and the following day divers will attach more chains and cables, while starboard sponsons will be lowered to their final position, previously inaccessible. Then the full refloat will begins, raising the Concordia, deck by deck.

If everything runs smoothly, it is possible the ship will be towed away on Saturday, earlier than scheduled.