Some of the world's most ambitious construction projects are currently blasting through mountains once thought entirely impassable.
By linking regions long severed by geography, these mega-tunnels aim to trigger a revolution for both travelers and global freight.
But with core tunnels opening years before the tracks connecting them are even built, a looming infrastructure bottleneck awaits.
AI-generated summary was reviewed by a CNN editor.
Europe wants to lure more people away from short-haul airlines and onto high-speed trains between its major cities. And as more and more travelers discover the joys of long-distance rail, there’s everything to play for.
