Roadside Shrines didn’t start until I moved to Arizona in 1995. My initial thought was this was something unique to the U.S. southwest. In 2015 I spent time in the Atacama Desert in Chile, and realized that this was a more wide-spread cultural manifestation than I had thought. Since these are the only two places in my travels where I have seen these memorials in this kind of density, my assumption is that this is primarily a Hispanic and Catholic expression.