It might seem an unlikely place to be growing fruit, but deep beneath a South Korean mountain, a high-tech farm has been built inside an abandoned tunnel.
Once a functioning highway in the province of North Chungcheong, the tunnel's sharp curve was deemed dangerous, so in 2002 it was closed and a more gently curved road was constructed nearby. Now this 2,000-feet-long (600 meter) tunnel is being used to grow salads, leafy greens, and strawberries.
It's an example of "vertical farming" -- a method of growing food without soil or natural light, in vertically stacked beds in a controlled environment. With no natural sunlight, here, LED lights are used to grow crops all year round.
They're also what give the farm its pink glow -- they emit only the spectrum of light that plants use to photosynthesize. More unusually, the music of Beethoven and Schubert is piped into the tunnel, because it encourages the produce to grow, according to Choi Jae-bin, CEO of NextOn, the company that created the farm.