Tirantes Bridge, Cable-stayed bridge in Pontevedra, Spain

Tirantes Bridge is an asymmetric cable-stayed bridge over the Lérez River in Pontevedra, with a 125-metre span between pillars and no intermediate supports. A single 63-metre leaning concrete pylon stands at one end, not mid-span, and 17 pairs of steel stays fan out from it: front stays hold the 20-metre-wide concrete box-girder deck, rear stays anchor to two concrete bases as counterweights.

Planned by the Xunta de Galicia in the early 1990s to open the north-east of Pontevedra on drained marshland, the bridge was designed by Leonardo Fernández Troyano and Francisco Javier Manterola Armisen, with the competition decided on 15 December 1991. Construction began in April 1993 under chief engineer Arsenio González Losada, using successive cantilevers because of tides of over 4 metres. A load test with 16 trucks on 13 May 1995 preceded its opening to traffic on 26 May 1995.

The bridge's name comes from its steel stays, which reflect in the Lérez and hum in the wind. Since 2013 one of its four traffic lanes has been a bicycle path, and the crossing links the Congress Hall area with the north bank of the river.

The bridge accommodates vehicles, pedestrians, and cyclists with a separate bicycle path available. Visitors should know that conditions may vary depending on tidal changes in the river below, which can affect water levels significantly.

The 63-metre pylon leans and is anchored by 17 pairs of steel stays, the rear ones tied to two concrete bases on the ground that act as a counterweight. In wind the stays sway and produce a characteristic noise, and their reflection in the Lérez is a detail visitors often photograph.