Anyone who's driven along the main road between Tainan County and Chiayi City will have seen it. If you've taken the train — the slower conventional train that is, not the high-speed railway — between Chiayi and points south, you'll likely have noticed it. It looks somewhat like a water tower, but with windows. Some people think it resembles a flying saucer on legs; others describe it as “a giant concrete mushroom.”
It's the Solar Exploration Center in Chiayi County's Shueishang Township. This impossible-to-miss landmark is located a few meters east of Taiwan Highway No. 1 (a road which many locals still refer to by its old name, the 'Sheng-dao,') and just to the west of the main north-south railroad.
This site is of geographical significance: It's where the Tropic of Cancer cuts across Taiwan. Those parts of the island north of the Solar Exploration Center are, officially, sub-tropical. The one-third of the island that lies to the south is within the hot, humid Tropics. So why is the Solar Exploration Center here, and not someplace else? Why not on the east or west coast, or on the southern slopes of Yushan? Taiwan's highest mountain peak is a mere two-and-a-half kilometers north of the Tropic of Cancer.
The reason has to do with the adjacent railway line. After Japan seized control of Taiwan in 1895, work on the north-south rail link, which had begun in the 1880s, was speeded up. In 1908 the railroad reached the Tropic of Cancer. To celebrate this achievement a commemorative pillar was erected...
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