The country traditionally associated with smashing old plates outside friends' homes on New Year's Eve is Denmark.
The custom involves throwing unwanted plates and dishes against the doors of friends or neighbors. A large pile of broken crockery was traditionally interpreted as evidence that a household had many loyal friends, although the practice is less common in modern Denmark than it once was. Some accounts also connect the act with getting rid of old household items before the new year.
Danish New Year's celebrations include other distinctive customs, such as jumping from a chair at midnight to symbolically leap into the new year. People may also eat a traditional ring-shaped cake called kransekage and drink champagne. The plate-smashing practice is often confused with general Scandinavian New Year customs, but Denmark is the country most specifically linked with this door-to-door tradition.