Answer: The postal codes in the Netherlands consist of 4 numbers and 2 letters. These postal codes go with addresses instead of the whole city. The first two digits represent the town; the last two digits and the letters represent the part of the street. A number of homes can have the same postal code. For instance:
a postal code starting with 30: Rotterdam
a postal code starting with 10: Amsterdam
The Delft postal codes range from 2611 to 2629. In written addresses the postal code has to be put before the name of the city.