Engineering marvels: A look at the world's most impressive bridges
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Hong Kong-Zhuhai-Macao Bridge
The Hong Kong-Zhuhai-Macao Bridge, which was inaugurated in October, is the longest sea-crossing bridge in the world.
The 55-km bridge can withstand earthquakes and typhoons and a section is deep underwater so that shipping routes are not disturbed.
Here is a look at some bridges - smaller but engineering marvels on their own - that move to make way for boats and ships.
Agencies
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The Gateshead Millennium Bridge, England
Opened in 2001 The pedestrian and cyclist tilt bridge over the Tyne in Tyneside is sometimes referred to as the Winking Eye Bridge due to its shape.
Three hydraulic rams on either side lift the 126-m bridge so that small ships can pass underneath.
The bridge also cleans up its own litter - anything dropped on the deck automatically rolls into special traps at each end of the bridge each time it opens.
Agencies
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Submersible Bridges, Greece
Opened in 1988 The Corinth Canal cuts through the narrow Isthmus of Corinth and separates the Peloponnesian peninsula from the Greek mainland, connecting the Gulf of Corinth with the Saronic Gulf in the Aegean Sea.
It saves ships a 700-km journey around the Peloponnese. Two bridges at each end of the canal can submerge 8 m below water level to permit waterborne traffic.
Agencies
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Scale Lane Footbridge, England
Opened in 2013 The pivoting design of the 57-m bridge in Hull allows public to stay on it while it swings open and close for river traffic.
Seating arrangements and a light-and-sound installation add to the experience.
Agencies
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Rolling Bridge, England
Opened in 2004 The 12-m bridge that provides access to the Grand Union Canal in London's Paddington Basin can curl into a circle.
Agencies
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Puente de la Mujer, Argentina
Opened in 2001 Located in Buenos Aires, Argentina, the structure has a single mast with cables suspending a portion of the bridge that rotates 90 degrees to allow water traffic to pass.
The 102.5-m middle section of the 170-m bridge swings.
Agencies
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Pont Gustave-Flaubert, France
Opened in 2008 This vertical lift bridge across the Seine in Normandy is 56 metre tall and 55 metre long.
Its deck is lifted straight up by a butterfly-shaped pulley system so tall ships can pass through. It takes 12 minutes to raise the section.
Agencies
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Slauerhoffbrug, Netherlands
Opened in 2000 Also known as the Flying Drawbridge, the fully automatic bridge in Leeuwarden, the Netherlands, has a multi-storey pylon that hoists a 15 m x 15 m piece of the road into the sky for boats to pass.
The road is automatically lowered back so that traffic can resume on the bridge.
(Source: National Geographic, Mental Floss, BBC, Popular Mechanics)