Trans-Siberian Railway

THE ANSWER
"Trans-Siberian Railway route" — Photo by Russia_edcp_location_map.svg: Uwe Dedering derivative work: ויקיג'אנקי / Wikimedia Commons / CC BY-SA 3.0
The longest thread ever stitched across a continent.
This engineering marvel connects Moscow to the Russian Far East. It remains the most famous train journey for those looking to traverse a vast landscape.
Explanation
Did you know?
The entire journey crosses eight different time zones.
The 5 Clues
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“It was once described as the iron backbone of an empire.”
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“Construction spanned the turn of the twentieth century through difficult terrain.”
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“A journey on it requires a significant supply of books and patience.”
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“It bridges the distance between Europe and the Pacific Ocean.”
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“The world's longest train line traversing the breadth of Russia.”
lightbulbAvg Clues to Win
4.3/5
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35%