The City of Boston is once again on the receiving end of an annual Christmas tradition.

After the devastating Halifax Explosion on Dec. 6, 1917, the city of Boston kindly assisted in the aftermath of that horrible day by sending medical personnel and supplies.

The following year, Halifax sent a Christmas tree as a thank you for their help.

In the early 70s, the city decided to do it again, and has kept up the practice ever since.

This year’s tree made a 1,000 km trek from the peace and quiet of Lorne, N.S. to the hustle and bustle of downtown Boston.

Bill and Andrea MacEachern donated their 15 metre white spruce, that is about 72 years old.

Just as the tree stands high in the Boston Commons, reminding residents of the appreciation and kinship Halifax feels for this city, at noon hour Thursday, the Nova Scotia flag was raised high above Boston City Hall.

“We celebrate the tradition and the special bond the cities have with the events that we have today,” says Marty Walsh, Boston Mayor. “Not only with the lighting of the Christmas tree, the beautiful tree that came down from Nova Scotia, but also by raising the flag we show our appreciation back. Whether it is through the flag raising, tree lighting or any other way we can celebrate the gesture of good will.”

Thousands of people are expected to attend the tree lighting ceremony on the Boston Common and hundreds of thousands more will be watching it at home on TV.