ROCKFORD, Ill. (WTVO) — Passerby may have noticed the placement of an undecorated Christmas tree atop the skeletal structure of the forthcoming Rockford Public Library building downtown, and wondered: what it’s doing there?

The library is currently building a brand new, state-of-the-art facility in its former location along the Rock River at 215 Wyman Street. 

The Wyman building was demolished as part of a clean-up effort, to mitigate exposure to potentially hazardous chemicals in the soil, left over from a prior industrial site on the property.

Currently, the library is in a temporary location, at 214 N. Church Street.

A final steel beam, signed by Rockford residents, was the final piece added to the skeletal structure on October 27th.

The tree is known as a “topping tree,” an “ancient construction tradition,” according to Slate, that goes along with other rituals such as the laying of foundation stones and ribbon cuttings.

The tree is associated with “topping off” the highest beam of a structural element.

Slate adds that in 8th-century Scandinavia, workers used sheaths of grain for their topping-off ceremonies.

The new library is scheduled for completion by the end of 2023.