AUGUSTA, Maine — One million balsam wreaths aboard a tractor-trailer caravan are on their way to the nation’s most hallowed ground, Arlington National Cemetery, the final resting place for more than 400,000 active duty U.S. service members, veterans and their families.

The “Wreaths Across American” convoy departed Saturday from Columbia Falls, Maine, where the wreaths are made, and will stop at schools, memorials and veteran group gatherings along the 740-mile journey to Arlington, Virginia.

The tradition began when Maine wreath maker Morrill Worcester donated 5,000 wreaths to Arlington Cemetery. Since then, it’s grown each year.

The wreaths are set to arrive on Dec. 15 at the national cemetery, where volunteers will place the greenery on headstones.

Copyright 2018 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.