Ambrosia, also known as the City of Harmony, is a city shown in the movie Professor Layton and the Eternal Diva. Rumors circled about Ambrosia being the key to the secret of Eternal Life. It is one of the Azran Legacies sought after by Targent, however this is not known until Professor Layton and the Miracle Mask.
Legend has it that a beautiful queen once lived in Ambrosia who had a burning passion for music and was loved by every resident in the city. When she became ill, residents did all they could to save her from the horrid illness by attempting to make an elixir that would save her life. Unfortunately, this was not made in time and the queen passed away. The Elixir that was made by the residents was labeled as 'The Elixir Of Eternal Life'. All of the residents took the elixir, hoping that they could be with their queen once more.
Included in the legend is instructions on how to revive Ambrosia. This can be done by playing all of the songs of Ambrosia all at the same time. To make this a reality, Jean Descole kidnaps Melina and makes her sing The Song Of The Sea. On the other hand, Descole played The Song Of The Stars. The plan goes against the legend and fails to make Ambrosia rise. Enraged, Descole transforms his castle and the Detragon into a large robot in an attempt to force Ambrosia to rise.
What Descole failed to realize was that there was a third song that needed to be played, The Song Of The Sun, as Professor Layton points out. Layton asks Melina to sing The Song Of The Sea whilst he played The Song Of The Sun and The Song Of The Stars at the same time. This resulted in Ambrosia rising from the Island.