As the most recent phase of the CrossRoads project, the Trestle Stair repurposes a historic rail trestle rising gently along the valley edge as a public promenade and event space, connecting the Marsupial Bridge with Commerce Street below. The heavy timber structure that once carried freight trains now supports a concrete deck, integral benches and cantilevered overlook. The width of a rail car, the new deck allows the existing structure to read as both sculptural presence and historic remnant. Concrete stairs provide end connections, and an Ipe wood terrace extends to the adjacent hillside, enveloping a grove of native Quaking Aspen trees. The railing system is clad by a tessellated perforated stainless steel apron, integral LED lighting, and wood handrail. The project establishes a model for civic space and sustainable transportation through the functional and aesthetic transformation of abandoned industrial infrastructure.