Covering the mountainsides all around Rio de Janeiro are the illegal shantytowns known as 'favelas'.  Pam looks out on a portion of the largest one, Rocinha, where up to 200,000 people may live - and this is just one of hundreds of favelas.  Most favelas don't have roads, only narrow footpaths to navigate through.  In 2004, estimates were that 19% of the entire population of Rio lived in favelas!