Walt always loved horses. He first spent time with them in his childhood home of Marceline and they were a big part of his life and his animation from there on out. I think he understood how powerful that "clop-clop-clop" sound was when he put them on Main Street, U.S.A. on opening day in Disneyland and he would have approved of their being there in 1971 when Magic Kingdom opened its gates for the first time.
Nothing else works quite as well as hoofbeats to slow your mind down and put you in a simpler, small town America, turn of the century mindset.
Taken at 90mm in full daylight, cut a bit with an aperture of f/8 and a bit more with a shutter speed of 1/400. ISO 100.