Lesson 01
Latitude from the north celestial pole
Latitude is the altitude of the celestial pole above its horizon. In the north, Polaris sits near that pole — so its height above the north horizon is about your latitude. Equator: on the horizon. Pole: overhead. Polaris never rises south of the equator.
Not only pole stars: Sun, Moon, planets, and tabulated stars with exact time give lines of position in either hemisphere.