A wedding anniversary is the anniversary of the date a wedding took place. Traditional names exist for some of them: for instance, fifty years of marriage is called a "golden wedding anniversary" or simply a "golden anniversary" or "golden wedding".

The names of some anniversaries provide guidance for appropriate or traditional gifts for the spouses to give each other; if there is a party these can be brought by the guests or influence the theme or decoration. These gifts vary in different countries, but some years have well-established connections now common to most nations: 5th Wood, 10th Tin, 15th Crystal, 20th China, 25th Silver, 30th Pearl, 35th Jade, 40th Ruby, 45th Sapphire, 50th Gold, 60th Diamond, and 70th Platinum.

The modern tradition may have originated in medieval Germany where, if a married couple lived to celebrate the 25th anniversary of their wedding, the wife was presented by her friends and neighbours with a silver wreath to congratulate them for the good fortune that had prolonged the lives of the couple for so many years.

The symbols have changed over time. For example, in the United Kingdom, diamond was a well known symbol for the 75th anniversary, but this changed to the now more common 60th anniversary after Queen Victoria's 60 years on the throne was widely marked as her Diamond Jubilee.

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