This is Amsterdam, and this is my Bike!
Amsterdam Loves Bikes
The colors of the flag are derived primarily from the coat of arms of the City of Amsterdam, or rather from the shield in it. The meaning of the colors is unclear. According to the City of Amsterdam, its origin could go back the coat of arms of the Persijn family, which once owned a large tract of land in the capital.
In the coats of arms of two other Dutch cities, Dordrecht and Delft, the middle stripe symbolizes water. In regards to Amsterdam, this black strip becomes the River Amstel. These colors as well as the crosses are to be seen in the flags of both Ouder-Amstel und Amstelveen.