La Boca is an area of Buenos Aries, one of the oldest parts of the city and the location of the first port/dock.
Many of its early settlers were from italy and across europe.
The area is famous for its brightly coloured houses, tango dancing in the street and Argentinas premier football team The Boca Juniors.
The reason for the bright coloured houses is that the locals painted them with whatever paint was left over from painting the boats in the docks.
It is a very touristy couple of blocks in an otherwise fairly unsavoury part of the city, nice to visit to take some interesting photos but not really worth sticking around unless you have tickets for the football.