Houston-based DC Partners has crossed a key milestone in the company’s effort to open the Allen Parkway corridor's first combination condominium-hotel tower.

The company hosted a Jan. 13 topping out ceremony for The Residences at The Allen, the centerpiece of DC Partners’ $500 million mixed-use development at 759 Gillette St.

During the ceremony, DC Partners officials signed a steel I-beam with celebratory messages to honor the occasion. The I-beam was later installed in the building as part of a tradition to bring good fortune to the project.

When it opens next year, the 35-story tower will have a 170-room Thompson Hotel occupying the first 15 floors of the building and 99 condo units on floors 16 through 35. Condo residents will have access to a private lobby, the hotel’s concierge service, an on-site restaurant and a seventh-floor amenity space and outdoor pool deck.