International Olympic Committee president Thomas Bach has praised the "amazing" transformation that has taken place in the Russian town of Sochi.

The Black Sea resort saw infrastructure and facilities built from scratch as part of Russian president Vladimir Putin's goal to turn the region into a winter sports center and year-round tourist destination.

Sochi was awarded Russia's first Winter Games in 2007 after two previous unsuccessful bids, with Bach serving as the chairman of an International Olympic Committee evaluation panel that assessed the city's second failed attempt.

"It's amazing what has happened here," he told reporters. "I [originally] came here and said: 'Impossible'. We were here and you saw [an] old, Stalinist-style sanatorium city where you entered the room and you were looking at the roof so you would not be hit by something falling down. It was terrible.

"And then seeing now. It was really amazing. And now it will be important to secure the legacy of this games."

The Sochi Winter Olympics are rumoured to have cost around £30bn.