Rotterdam’s motto is probably the most well-known city motto in The Netherlands. Also because it’s used by the most succesful football club of Rotterdam, Feyenoord. The motto was granted by Queen Wilhelmina in 1948 to remember the role of the citizens of Rotterdam during World War II. A war in which no Dutch city suffered as much as the city of Rotterdam. The motto granted was Sterker door Strijd which translates to Stronger through Effort. The American town of Rotterdam in the state of New York also uses this motto.
The flag of Rotterdam
The flag of Rotterdam is a horizontal triband of green-white-green and was adopted 10 February 1949. The green and white colours have been used to represent the city since the Middle Ages, but the number of stripes has varied greatly. The green refers to the Court of Wena (a medieval castle) and the white symbolises the Rotte river. The autonomous region of Andalusia in Spain has the same flag as Rotterdam. Eventhough that flag is sometimes used with a crest on it. The flag of Nigeria is also a green-white-green triband, but vertically. In Rotterdam you sometimes see shops owned by Nigerians flying both flags, the horizontal and the vertical version. For more fun information on flags in general visit our friends from Flag Freaks.
The coat of arms of Rotterdam

The motto and flag are both found in the coat of arms of Rotterdam. Also to be found on the shield in the coat of arms are 4 lions. The shield was given by William I, Count of Holland and Hainaut in thanks for the support of the lords of the Court of Wena in its fight against Flanders in 1304. The lions are the two red Dutch lions and two black Hainaut lions. A red lion on a yellow background is also found on the flag of South-Holland, the province of which Rotterdam is the biggest city.