<P> The Amazing Race 18 (also known as The Amazing Race: Unfinished Business) is the eighteenth installment of the reality television show The Amazing Race . The Amazing Race 18 featured eleven teams of two--each returning from a previous edition for the first time since Season 11--in a race around the world for a $1 million prize . </P> <P> The eighteenth cycle started on Sunday, February 20, 2011 . It aired on CBS in the United States on Sunday nights at 8: 00 pm ET / PT with the two - hour season finale on May 8, 2011 . The show is hosted by Phil Keoghan . </P> <P> Sisters LaKisha "Kisha" and Jennifer "Jen" Hoffman were the winners of this edition of the race . For the second season in a row, an all - female team wins the American edition of the competition . </P> <P> The Amazing Race 18 was the first season of the United States series to be broadcast on high - definition television . While most other prime - time television shows have transitioned to high definition, including other reality television shows, previous seasons of The Amazing Race have used standard - definition television due to the cost and fragility of high - definition recording equipment . International versions of The Amazing Race, including the fourth Asian and second Latin American seasons, had already transitioned to high - definition . Also, many previous editions of Elimination Station were filmed in high - definition . This season of the Race traveled a little over 40,000 miles (64,000 km) across 23 cities and five continents . </P>

Who wins season 18 of the amazing race