Installation of railway archway above Kerch Strait is key phase in Kremlins plan to integrate peninsulas confiscated from Ukraine

Russian engineers have completed a key stage of a bridge that will link the annexed Crimea peninsula to mainland Russia.

A huge 6,000 -tonne railway arch was hauled into place 35 metres( 115 ft) above the sea, in an operation involving hundreds of workers.

The bridge, which will be 12 miles long when complete, is due to open to road traffic next year and rail trafficking in human 2019. It is a major part of the Kremlin's plan to integrate Crimea, seized from Ukraine in March 2014 in a rapid military operation. The international community still regards the territory as part of Ukraine, and Crimean officials and companies have been under western sanctions since the annexation.

Crimea is linked to Ukraine by a narrow isthmus, but is separated from Russia by the Kerch Strait. Currently the only routes to Crimea from mainland Russia are by airliner or a ferry across the strait, which is often cancelled due to bad weather.

For Russia, the bridge is both a practical necessity to provide infrastructure links to the annexed peninsula, and a symbolic move meant to show that Moscow has no purpose of giving up control over Crimea any time soon. Russian officials hope the bridge will make it easier for Russian tourists to vacation in Crimea, and for Crimean wines and produce to be transported to mainland Russia for sale.

Kerch Strait bridge

The railway arch forms a section more than 200 metres in duration, and is high enough to allow ships to pass beneath. A similar archway for the road traffic section will be lifted into place next month. The bridge has been described as the most complicated construction operation in Russian history. It will be the longest bridge in the country, and is projected to cost nearly PS3bn.

Plans for the construction industry began to take shape shortly after the annexation, and were made all the most important by a series of blockades from the Ukrainian side. The perimeter between Crimea and the rest of Ukraine is highly militarised and subject to long delays. The peninsula was left without energy for weeks on end in late 2015 after Ukrainian vigilantes blew up energy lines.

The construction marks the realisation of plans that have been floated for more than a century, beginning with a vague suggestion by a British consortium in the 19 th century to build a rail link between London and India via Crimea.

Plans were induced for a bridge during the 1930 s industrialisation drive under Joseph Stalin, and in 1942 when Crimea was under German control the Nazis got as far as beginning construction on a bridge, but were repulsed by the advancing Red Army before they could complete it. A one-track rail bridge was built by the Soviets towards the end of the second world war, but collapsed just a few months later.

Later Soviet plans were abandoned due to the huge cost involved, given the complicated geological concerns in the area and difficult weather conditions.

After the annexation, Russian officials looked at various options for connecting Crimea to the Russian mainland, including a passageway, but eventually settled on a bridge.

Construction is being overseen by Arkady Rotenberg, a billionaire who was Vladimir Putin's childhood judo partner and has a long history of winning country construction contracts during the presidency of his old friend.

Rotenberg has claimed the project is not just about money:” Besides fiscal gain … I also want the project to mean something for future generations ,” he told Russian nation television last year.

Russia says its seizure of the territory was in response to the will of locals, who voted overwhelmingly to join Russia in a hastily organised referendum in 2014 that was dismissed as illegitimate by the international community. Since then, human rights groups have criticised a crackdown on freedom of speech in individual regions, and the indigenous Crimean Tatar population has reported harassment and arrests.

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