Oddly enough, I saw a performance of 'Much Ado' on Thursday night, done in precisely this fashion in the 123 acre Nichols Arboretum in at University of Michigan. Not quite Central Park, but we did have to walk a fair distance between some of the scenes, including treks up grassy hills and lots of steps.
The small medieval/reniassance singing group I'm in sang a few songs before the play began for the opening night, and got to stay and see the play for free. Mind you, I could have done without having to sing immediately after the brisk 10 minute walk, up and down steep hills part of the way, to get to the starting location. I had to breathe more often than usual, which wasn't ideal since I was alone on the alto or second soprano line on at least 2 or three of the songs (There were only 4 of us there, since the other 3 regulars had other commitments that night). Ain't exercise induced asthma great (not). We'll be going back in greater force to sing before the performance on the 14th (which was the best Saturday for everyone), and I'll make sure we meet earlier, and preferably at the starting location rather than at the gate.
I was glad they'd warned us to wear good walking shoes, and to bring chairs or blankets to sit on. The play was quite well done. They had almost no set type scenery, but rather used the trees very creatively (particularly in the scenes in which people are overhearing things and reacting to them).
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