That sounds just amazing. I bet you wished you had your camera with you then. I would have done the same as you... just stand there to try to not scare it away.
I used to have similar times with a red-tailed hawk in my backyard when up in Wisconsin. It would sit high up in a mulberry tree and just watch the open grass area for something to swoop down and grab. It eventually got used to some activity around it, it would start yelling at my mother-in-law if she came out and got too close, and didn't fly away most times.
I really miss those times.