Día del Amigo

Día del Amigo (Spanish, Friend's Day) is a celebration of friendship, held annually on July 20 in South American countries including Argentina, Paraguay, and Uruguay.
History

The idea for Friend's Day goes back to Argentine teacher, musician, and dentist Enrique Febbraro, who lobbied to turn the anniversary of the first moon landing into an international day of friendship,[1] along with his Rotary Club de Once, Buenos Aires. He argued that on this particular day, the whole world had been friends of the three astronauts. The first official recognition of the day came with decree No. 235/79 by the government of Buenos Aires Province, which authorized the celebration and gave it official nature.
Argentina

In Argentina, Friend's Day is often a good excuse for a common friendly gathering, though people also employ the day to get in contact with old and seldom-met friends and greet them. Since it is not a public holiday in Argentina, the gatherings tend to happen during the evening.
Friend's Day has in recent years turned into a very popular mass phenomenon. In 2005, the amount of well-wishing friends led to a temporary breakdown of the mobile phone network in the cities of Buenos Aires, Mendoza, Córdoba and Rosario, comparable to the one experienced in 2004 on Christmas and New Year's Day. Seats in most restaurants, bars and other establishments are already completely booked a week before the celebration.
Brazil

Dia do Amigo (Portuguese: Friend's Day) is April 18.