"Taps" is a traditional tune of remembrance for those who gave their lives in the service of the United States.
The event is scheduled for Friday at 2.46 pm local time, the moment the first plane struck the World Trade Center 25 years ago to the day.
The September 11 terrorist attacks caused the deaths of 2,996 people. Six people of Polish nationality or descent were among the victims.
The tower of St. Mary’s Basilica is the place from which the famous Kraków bugle call (hejnał in Polish) is played every hour on the hour.
(mk/jh)