Featuring an angular white pylon with a shape that has been compared to a swan, Ben van Berkel's Erasmus Bridge in Rotterdam is the latest addition to the Dezeen A-Zdvent calendar.

The 800-metre-long cable-stayed bridge spans the Meuse river, connecting Rotterdam south with the city centre. It was completed by Van Berkel in 1996, before he and wife Caroline Bos changed the name of their office from Berkel and Bos to the better known UNStudio.

The 139-metre-high pylon is a prominent silhouette on the city skyline, thanks to its unusual shape. Rather than consisting of a simple vertical, its base runs parallel with the ground surface, then folds up at an angle before eventually bending up straight. Its silhouette has been compared to a swan.

UNStudio describes it as "a bracket construction in sky-coloured steel [that] can appear thin as a needle, or wide as a harp".

The bridge's four spans – the longest measuring 280 metres – create two footpaths, two cycle paths, tram rails, and two lanes for road traffic. Thirty-two stays attached to the top of the pylon take the majority of the weight, supported by eight backstays and five concrete piers.

The southernmost span features an 89-metre-long bascule, a section that folds up to allow large ships to pass.

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The Erasmus Bridge celebrates its 20th anniversary in 2016. Since its construction, the area around it has been populated by a host of buildings by well-known architects, from Renzo Piano's KPN Tower (2000) and Mecanoo's Montevideo Tower (2005), to Alvaro Siza's New Orleans (2010) and OMA's De Rotterdam (2013).

Van Berkel gained his experience in bridge design from a spell in the office of Santiago Calatrava, although he has completed only a few under his own name. Others are the Prince Claus Bridge in Utrecht and the Bascule Bridge in Purmerend.

In the spirit of an advent calendar, Dezeen will publish a bridge every day until Christmas, one for each letter of the alphabet. See all the ones revealed so far »

Images courtesy of Shutterstock, unless otherwise stated.