The city government of Buenos Aires has legalized same-sex marriage for tourists and non-residents. Via press release from Federación Argentina LGBT:
La Federación Argentina de Lesbianas, Gays, Bisexuales, y Trans hails the decision of the municipality of Buenos Aires to eliminate the administrative obstacles that prevented the marriage between two foreigners, a right guaranteed in Article 20 of the Constitution. Thus, the City of Buenos Aires has become the fourth district in the country to authorize such marriages after the provinces of Santa Fe (where Paraguayan activists Simón Cazal and Sergio López were married), Tierra del Fuego, and Buenos Aires. Australian activists Alex Greenwich and Victor Höld were just married this past Friday in the latter province.
Same-sex marriage became legal in all of Argentina in 2010.