Tango dancers, fans converge on Buenos Aires

The Tango Buenos Aires Festival and Dance World Cup 2013 draws the world's top Tango dancers - and top Tango fans -- Aug. 13-27, 2013.

The competition features 500 couples from 37 countries, including China and Pakistan, according to Prensa Latina.

It takes two to tango - but those two can be men or women in any combination.

Of the 500 couples in the 2013 competition, four are same-sex couples -- allowed to compete for the first time this year. Three of the couples are men and one of the couples is female, according to the Spanish-language publication, Clarin.com .