Old plates are the household objects famously smashed against friends' doors in a Danish New Year's Eve tradition.
People traditionally save unwanted or chipped crockery and throw it against the doors of friends and neighbors. A large pile of broken plates is interpreted as evidence that a household has many friends willing to visit and celebrate with it. The custom is often described as a noisy expression of goodwill rather than simple vandalism.
Modern practice varies considerably. Some people no longer break dishes because of cleanup, safety, or changing social habits, while others treat the tradition as a playful activity. Danish New Year's Eve also commonly includes a midnight toast, festive food, fireworks, and the televised New Year speech from the monarch.
The plate custom should not be confused with breaking a glass at a wedding or with Greek plate-smashing traditions, which have different cultural histories. In Denmark, the objects are specifically old or unwanted plates and the target is traditionally a friend's door.