It was constructed in 1904 to pass over the Fremantle railway line, with the horseshoe shape designed to fit the approach ramps into a constricted site.

The main structural elements of the bridge are of steel, and it is supported by a series of semi-circular arches with rendered decorative treatment.

Many of the arches on the Wellington Street elevation have been enclosed with glass, which in the past created shop fronts to retail spaces behind.

The winding form adds vitality to the Perth railway station precinct and the architecture contributes to the streetscape of Wellington Street.

As the line effectively cut the city off from its northern suburbs, a number of bridges and level crossings had to be built to connect the two areas.

In a site with no land for approaches, the shape of the proposed William Street bridge was chosen as the only viable option for achieving the necessary gradients for horsedrawn vehicles.