Clint Eastwood movie riding horse toward settlement Concierto de Aranjuez 2nd movement playing, what is the movie?

My Mum has a memory of a western in which Clint Eastwood is riding his horse toward settlement (as if to save them), the music from Concierto de Aranjuez 2nd movement is playing.  She loved the music and wants to watch the film again.  Does anyone know what is the movie?  Three of us are hunting online with no clear answer, can you help as she is driving us all crazy!