That enclosure looks just great!! Bet the kitties love it. I especially like the sisal post leading to the higher level. How creative!

MomToThree - I have no idea how you could keep neighboring cats out of your yard. I don't think that is possible. We also have a yard with a privacy fence - yet there are several cats who visit regularly and sometimes "fight" with my cats at the open windows. I can't even raise the windows very high because I think they could easily tear the screening if they were protecting their turf. Maybe you could let your kitty in the yard only when you are outside with them?