Walk by an alleyway in Sydney's Angel Place and experience a whimsical audio-visual installation created by artist Michael Thomas Hill. This piece was first displayed in 2009 titled "Forgotten Songs" and has 110 empty birdcages suspended in the air, playing the songs of fifty birds that once lived in central Sydney before urbanization of the area. The sounds change from day to night so you can hear the daytime birds songs in contrast to the nocturnal birds. The installation proved to be so popular that city dwellers requested for it to remain as a permanent piece. Now there are 180 new rustproof cages with 10 speakers playing the songs of 50 bird species, you can also find the names of the birds engraved on the paved stones beneath the cages.