My first tropic

I have crossed both several times, but by air.  This is the first time I am actually able to pinpoint the 23.5 degrees south of the equator that defines the Tropic of Capricorn. 

Actually, 23.5 is a generalization, as it is gradually shifting in a northward direction. The Tropic of Capricorn marks the line of latitude south of the equator (there is an identical line north of the equator, the Tropic of Cancer) where the longest day of the year, the December solstice (or June for the Tropic of Cancer), has the Sun directly overhead.