Who is building what in Sochi for 2014 Olympics

The cost of the 2014 Winter Games in the Russian city of Sochi now stands at $51 billion, making it the most expensive Olympics in history. More than half of the bill is being footed by Russian state-controlled companies and business tycoons. A look at what the major players are building in Sochi:

THE RUSSIAN GOVERNMENT

The government is building five of the six arenas in the coastal cluster, which will host indoor competitions such as ice skating, for about $10 billion. Deputy Prime Minister Dmitry Kozak, who is overseeing the Sochi preparations, said the government will spend a total of about $18 billion before the games begin in February 2014.

GAZPROM

The world's largest natural gas producer, a publicly traded company, has many Olympic projects in Sochi, including building a cross-country skiing and biathlon center, one of the three Olympic villages and an Alpine ski resort. Gazprom is also building a power station in a Sochi suburb for about $740 million and a pipeline to bring gas supplies to the Sochi area for about $1 billion. The total price tag for Gazprom stands at roughly $3 billion.

POTANIN

Metals tycoon Vladimir Potanin, whose fortune is estimated at $14.3 billion, started building the Roza Khutor ski resort before Sochi was picked to hold the 2014 Olympics. Infrastructure required by the International Olympic Committee cost $500 million, boosting his total bill in Sochi to $2.5 billion. In addition to the Alpine ski runs at Roza Khutor, Potanin's holding company, Interros, has built an Olympic village and a snowboarding and freestyle park.

DERIPASKA

Metals tycoon Oleg Deripaska, estimated to be worth $8.5 billion, is mainly involved in infrastructure development in Sochi. His holding company, Basic Element, is building an Olympic village, a sea port and has just finished revamping the Sochi airport. Basic Element expects to spend a total of $1.4 billion in Sochi.

SBERBANK

The state-controlled bank is set to spend at least $1.3 billion building a media center in Sochi, as well as a ski jump complex.