Dubai’s ruler has officially launched tunnel boring operations and drilling works for the Dubai Route 2020 metro during a visit to the site on Tuesday.

The Vice President, Prime Minister and Ruler of Dubai, His Highness Sheikh Mohammed bin Rashid Al Maktoum also reviewed the interior design of the new rolling stock of the Dubai Metro and the progress of the project while at the Discovery Gardens site, according to WAM.

Once complete, tunnelling will add 15km to the Dubai Metro Red Line from Nakheel Harbour and Tower Station to the site of the Expo 2020 Dubai.

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The tunnel boring machine used to complete the works, dubbed Al Wugeisha Expo 2020, is scheduled to pass across the underground station near Jumeirah Golf Estates by January next year.

The tunnel starts at Discovery Gardens and stretches 3.2km to The Green Community. It features depths ranging from 12.5 to 36 metres.

All tunnel drilling works will be completed by December 2018 with the first of the new Dubai Metro rolling stock arriving in July of next year.

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Construction work for the metro viaducts will be completed by next November and all railway works of Route 2020 will be completed in July 2019. The trail run for Route 2020 will start in February 2020.

His Highness was shown the new interior design of the Dubai Metro carriages, which are being manufactured in France under a contract for the supply of 50 trains: 15 for serving Expo 2020 and 35 for upgrading the service of the Dubai Metro.

While the exterior design of the new trains will remain the same, the interiors will be slightly altered to provide increased ease and access for future passengers.