San Francisco saw the 34th America's Cup competition begin on Thursday (July 4) with an opening ceremony at a giant pavilion at the city's America's Cup park.
The park by the waterfront will be the focus of the onshore competition while the racing itself takes place in San Francisco Bay, inshore rather than offshore as previously in the tournament's history.
The defending champion is Oracle Team USA and three challengers: Team New Zealand, Artemis Racing (Sweden) and Luna Rossa (Italy) will dispute the Louis Vuitton Cup competition beginning on Sunday (July 7) to secure the right to challenge Oracle for the America's Cup itself.
The boats are AC72 catamarans which will use their wing sails to reach high speeds in the Bay. In October 2012 Oracle Racing capsized, breaking its wing sail. In May 2013, challenger Artemis Racing capsized in the Bay during training, and Olympic gold medallist Andrew Simpson was drowned.
Since then, there has been a revision of competition rules after a safety review but two challengers, Luna Rossa and New Zealand, are disputing some of the changes which they say favour the Oracle Team.
The showdown between Oracle Team and the successful challenger begins in September.
Presented by Adam Justice