Euro notes and coins were introduced.

On 1 January 1999, the euro officially came into existence as a legal, virtual currency used for accounting and electronic transactions.

It was first adopted by Austria, Belgium, Finland, France, Germany, Ireland, Italy, Luxembourg, Netherlands, Portugal, and Spain.

Euro notes and coins were introduced later, on 1 January 2002, replacing national currencies such as the Deutsche Mark and French Franc.

3 January 1999 was only the first trading day of the euro in financial markets, not its launch date.
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