From 2005 everyone who is 14 years or older needs to be able to show their ID (European ID card or passport) at all times. Whoever fails doing this when questioned by the police will receive a fine.
Smoking is banned in all public buildings, restaurants and bars. Most bars and restaurant have a specially designed smoking room. Even at open-air train platforms you are not allowed to smoke at non-designated areas. All smokers gather around special ashtray poles (look for the cigarette logo). To purchase a pack of cigarettes you need to be older than 16. To get cigarettes from a vending machine in bars and restaurants you need to get a special age-coin available at the bar if you are older than 16.
By Dutch law you have to be 16 to buy beer or wine and 18 to purchase hard liquor. You can purchase wine and beer in the supermarket and hard liquor from special liquor stores. Drinking on the street is not allowed. In city parks it is officially banned although usually tolerated. Safety Warning Rotterdam is generally quite safe but going into a quiet alleyway during the night is asking for trouble. Some people also feel uncomfortable walking over the West-Kruiskade or the 's Gravendijkwal when it’s dark out because there are junkies around and other types you wouldn't want to get bothered by. And lastly, please take special care of your belongings and valuables at train and subway stations, markets and on shopping streets.