Every year on the night after Thanksgiving, the 30-story Regions Center headquarters building in downtown Birmingham becomes a beacon of the season.

It lights up with designs portraying a Christmas wreath, a Christmas stocking and Christmas trees.

Construction on the building was finished in 1971, when it was shared by the First National Bank of Birmingham and Southern Natural Gas. A light tube was placed above every window starting on the fifth floor. A Sonat executive saw a building in Houston that had a similar “curtain wall” design used for a Christmas lighting display during the holidays, and he brought the idea to Birmingham.

Regions Bank has continued the tradition and it will light up the building starting tonight, according to an official release on the bank’s web site.

Crews begin working on the display in the weeks leading up to Thanksgiving by installing gel sleeves over the light tubes in all the windows that will be part of the display. They follow design grids showing them which colors go on which windows to form the Christmas-theme shapes.