Forgotten Songs is a public artwork by Michael Thomas Hill located in Angel Place, Sydney. The installation was part of the 2009 Sydney Laneway Temporary art scheme, afterwards, due to the popularity of the installation, in 2011, the project was turned into a part of the 9 million dollar permanent laneway installations.^[Read more about it on Wikipedia.

Source: These are not empty cages: these are free animals! For World Animal Day | STREET ART UTOPIA