That little thing in orange? It's a man working on the Gotthard Base Tunnel, the world's longest railway tunnel, which is currently being carved out underneath the Alps in Switzerland. "A miner climbs on excavated rocks after a giant drill machine broke through at the final section Sedrun-Faido, at the construction site," Boing Boing's Xeni Jardin wrote yesterday of this photograph. "Crossing the Alps, the world's longest train tunnel should become operational at the end of 2016. The project consists of two parallel single track tunnels, each of a length of 57 km (35 miles)."

When the tunnels have been completed and handed over to Swiss Federal Railways (SBB) for management, passengers will be able to zip between Zurich and Milan at 155 mph, significantly reducing current travel times.

Back in October, we shared a different image from inside the tunnel as our Picture of the Day.

View more Pictures of the Day.

Image: REUTERS/Arnd Wiegmann.

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