This month, Portland’s first new bridge since 1973 will welcome pedestrians, bikes, streetcars, and Milwaukie-bound MAX trains. Local photographer Bruce Forster—who has documented almost every new TriMet construction project since the early 1980s—snapped somewhere around 20,000 shots over the course of Tilikum Crossing’s four-year construction. The black-and-white images, many of them taken from a helicopter, highlight the unseen labor behind the sleek new span. “This thing is built by hand,” marvels Forster. “Every piece of rebar and foot of cable was literally handled. Every inch of concrete has been rubbed by hand. When you look at it from a distance, you don’t realize that.”

View 50 of Forster’s photos at the Tilikum Crossing: Built by Hand exhibition, opening September 12 at Milwaukie City Hall.