The Rion-Antirion bridge (Greek: Γέφυρα Ρίου-Αντίρριου) is a cable-stayed bridge linking the cities of Rion (near Patra on the Peloponnese) and Antirion on the western mainland Greece, thus connecting with the rest of Europe.
The recently opened bridge will dramatically improve access to and from the Peloponnese, which could previously be reached only by ferry or via the isthmus of Corinth at its extreme east end. It has a length of 2252 m (2882 m including the access bridges); as it consists entirely of five cable-stayed spans and four columns, it is the world's longest cable-stayed suspended deck. Its width is 28 meters -- it has two vehicle lanes per direction, an emergency lane and a pedestrian sidewalk.
This bridge is widely considered to be an engineering masterpiece owing to several solutions applied to span the difficult site. These difficulties include deep water, insecure materials for foundations, seismic activity and the probability of tsunamis, and the expansion of the Gulf of Corinth due to plate tectonics.
Its official name is the Charilaos Trikoupis Bridge. Charilaos Trikoupis was a 19th century Greek prime minister, and suggested the idea of building a bridge between Rio and Antirio; however, the endeavour was too difficult a technological feat at the time.
The bridge was planned in the mid-1990s. Site preparation and dredging began in 1998, and construction of the massive supporting pylons in 2000. With these complete in 2003, work began on the traffic decks and supporting cable stays. On May 21, 2004, the main construction was completed; only equipment (sidewalks, railings, etc.) and waterproofing remained to be installed. The bridge was finally inaugurated on August 7, 2004, a week before the start of the 2004 Summer Olympics in Athens -- and the Olympic torchbearers were the first to officially cross its length. One of them was Otto Rehhagel, the German football coach who won the Euro 2004 Championships for Greece. Another one was Costas Laliotis, the former Minister of Public Works during whose term the project was begun.
The total cost of the bridge was about € 630,000,000, mostly funded by the European Union, and it was finished ahead of its original schedule, which had foreseen completion between September and November 2004.
The structure was designed, and, for the most part, built by the French group Vinci, which will operate it under concession under its Gefyra (Greek for "bridge") subsidiary. The lead architect was Berdj Mikaelian.
Due to the peculiar conditions of the straits, several unique engineering solutions had to be found. The water depth reaches 65 m, the seabed is mostly of loose sediment, the seismic activity is significant, and the Gulf of Corinth is expanding at a rate of about 30 mm a year, thus the possibility of tectonic movements had to be taken into account. Thus, special construction techniques were applied. The piers are not buried into the seabed, but rather rest on a bed of gravel, which was meticulously levelled to an even surface (a difficult endeavour at this depth). During an earthquake, the piers should be allowed to move laterally on the seabed; the gravel bed absorbing the energy. The bridge parts are connected to the pylons using jacks and dampers to absorb movement; too rigid a connection would fail in the event of an earthquake, but the bridge should not have too much lateral leeway either, so as not to damage the piers. There is provision for the gradual expansion of the strait over the bridge's lifetime.
Cars passing the bridge have to pay a €10.00 toll, while different rates exist for lighter and heavier vehicles and frequent travellers. An €1.50 toll is applicable for motorbikes.