The Beach Boys didn't invent the surf music but they sure made it famous. I think their harmony was what made them apart from other surf musicians like Jan and Dean, although Jan and Dean had their own moments.
From Summer 1963 here's the Beach Boy tune that came out first on the LP Surfer Girl - 'In My Room.' I practiced the harmonies over and over again singing to this one. I even told my mom I wanted a bass electric guitar because of this song.