CyrusOne, a wholly owned subsidiary of Cincinnati Bell, has announced that the last steel beam was put in place at its Chandler, AZ, site—officially completing the framework for its 1-million-sq-ft “Massively Modular” Phoenix data center complex. In celebration of the incident-free construction of the steel skeleton, ironworkers hosted a traditional “topping out” ceremony to recognize the quality performance.

Often associated with bridges and skyscrapers, modern-day steelworkers carry forward the topping-out tradition from more domestic roots in history to recognize the important role their skills play in the pinnacle of a structure first being reached. The custom of placing a tree on a completed structure arrived stateside with early immigrants to America and celebrated barn-raisings and housewarmings. Carried over from European civilizations, the ceremony originally honored a tree spirit for the use of wood in homes or enlisted the blessing of the forest gods for fertile land and home.