Nanning to Beihai, the whole journey is 229 kilometers. Excluding the stopping time, the speed of the train is about 77 kilometers per hour.

From the South Pole to the North Pole, the straight-line distance is about 20,000 kilometers.

So it takes 20000/77=259.74 hours = 10 days, 19.74 hours.

It takes about 1 1 day to walk.