This Half Life foto contains
wrangler de caballo, wrangler, and caballo wrangler.
There might also be
camino de herradura, sendero de caballos, camino real, lippizan, lipizzan, lippizaner, lipizanos, lipizzaner, convention, caballo de silla, montar a caballo, montar, caballo de montar, and silla de montar caballo.