The siren settled near Warsaw, where she charmed the fishermen with her beautiful singing.
An evil tradesman caught her and closed her into a wooden house in the woods, planning to show her to people on the market for money.
But the fishermen freed her, and so she promised them to protect their city.
So she does till now, guarding Warsaw with shield and sword.

herb of Warsaw:
http://img329.imageshack.us/my.php?image=herb12oj3.jpg