The UEFA European Championship, commonly referred to as the Euro, is a prestigious football tournament held every four years. The most recent edition of the tournament, UEFA Euro 2020, was postponed to 2021 due to the COVID-19 pandemic. It started on June 11, 2021, and concluded on July 11, 2021.

To calculate the duration of the UEFA Euro 2020, we can subtract the start date from the end date:

End Date (July 11, 2021) - Start Date (June 11, 2021) = 30 days

Therefore, the UEFA European Championship 2020 lasted for 30 days.

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