Every year during the festive season, people of all ages who play the tuba, sousaphone, euphonium, baritone and their several variations gather for a rehearsal followed by a concert of Christmas carols that have been specially arranged for these instruments of the low register.
These events happen mostly in the US, but there are also Tuba Christmas concerts in Switzerland, several provinces in Canada (though, sadly, none in Ontario) and in Costa Rica. They are joyful events, often performed outdoors, even on ice, and draw many appreciative spectators.Somebody said that listening to a choir of tuba players is like having a sonic hug.
Here's a short video of the most recent concert in NYC, still at Rockefeller Square.
The next video is a bit longer. It tells the story of the beginnings of Tuba Christmas in Baltimore.