South Korea
A rail bike hurtles down the old coal line through pitch-dark mountain tunnels.
The rail bike picks up speed and the tunnel mouth swallows the daylight. Seven kilometres of abandoned coal-country railway run through darkness, over gorge bridges, and out blinking into mountain sun.
Jeongseon's Auraji rail bike runs 7.2 kilometres of the railway that once served Gangwon's coal industry, through unlit tunnels and across narrow bridges toward Auraji, in country so rugged rail was the only way through until the 2000s. The Five-Day Market has traded on dates ending in two and seven since the Joseon era, mountain herbs and all, and this valley is the homeland of the Arirang folk song tradition. Byeongbangchi's skywalk adds glass-floored vertigo over a 580-metre drop.
Family
The rail bike supplies a shared physical task before children choose lunch in the five-day market.
Friends
Pedalling pairs can rotate effort and arrive at Auraji with energy left for the market.
Couple
Ride the rail bike two-up, then walk the market lanes if the date ends right.
Gondre rice and buckwheat noodles are the market staples on days ending in two and seven.
The five-day market's mountain-herb stalls are the province's larder.

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