As a bonus stop by our tour guide, we encountered this large structure. I have heard of the Tropic of Cancer, but I did not know there are physical markers for it at 9 spots around the world with two in Taiwan alone.
You noticed the marker is divided into two. If you stretch yourself and place a foot on each side, you can say a part of you is in the tropics and the other part is in the "northern temperate zone" of the earth.
If you click to enlarge this worldatlas.com map, it shows that the Tropic of Cancer is 23.5 degrees north of the equator and the Tropic of Capricorn is 23.5 degrees south of the equator. The area in-between these zones is called "the tropics" where the seasons do not vary much.