Engineers have completed lifting a giant railway arch onto the support columns for a bridge to Crimea. The unique overnight mounting took place 35 meters above the Kerch Strait.

The operation took more than 12 hours and 16 650-ton lifting devices to install the 227-meter-long arch. It was hoisted with 700 cables closely observed by 30 engineers, surveyors and other personnel. On Tuesday, the constructors successfully completed the installment of the structure, saying the arch is now securely fixed on the supports.

READ MORE: Crimea connection: Time-lapse video of 6,000-ton railway bridge arch being floated into place

Navigation in the strait had been suspended while the lifting operation took place. Shipping traffic has now resumed with the cargo ship ‘Saint Aleksey’ making a debut crossing under the new arch on its way south from the Sea of Azov. Followed by a flotilla of nearly 50 other ships, the ‘Saint Aleksey’ gave a greeting signal.

Another arch will be built for the road section of what is to become a 19-kilometer-long (12-mile-long) bridge. Spanning the Kerch Strait, it will connect the peninsula of Crimea with mainland Russia. The first cars are expected to cross as soon as December 2018.