The opening ceremonies for the XXII Olympic Winter Games kicked off Feb. 7. By all reports, the Sochi Games will be the be most expensive in the history of the international sporting event, at an estimated $51 billion, while work on many of the venues is still being finalized in the days leading up to the events.
Russia won the bid for the event in 2007 estimating the Olympics would cost $12 billion. But the infrastructure and venues have run over budget. An unprecedented level of transportation infrastructure has been built, including roads, tunnels and public transport systems. The Sochi Light Metro, at $758.8 million, was built to connect Olympic park, the airport and other venues. In total the Russian government built 102 bridges, paved 228 miles (367 kilometers) of road and added a new terminal at the airport.
It's almost an Olympic tradition for host cities to spend far more than originally planned. Here's a look at the costs of the last five Olympic cities.