Copenhagen is the Danish capital traditionally associated with smashing old plates against friends’ doors on New Year's Eve. The custom involves throwing or breaking unwanted crockery at the homes of friends and neighbors, with a larger pile sometimes interpreted as a sign of popularity.
Danish New Year customs also include watching the monarch’s New Year speech, eating celebratory food, and jumping from a chair at midnight to “jump into” the new year. These practices vary by household and have changed over time, so not every resident follows every tradition.
The plate-smashing practice is often reported as a Danish custom rather than an activity limited to Copenhagen. Copenhagen is the relevant capital city when the question asks which capital is traditionally associated with it, but similar festive customs can appear elsewhere in Scandinavia and Europe.
Modern concerns about cleanup, noise, safety, and waste have made the practice less universal than popular descriptions suggest. It should not be confused with Denmark’s separate tradition of lighting fireworks on New Year’s Eve.