Cooperstown cotillion

I'm doing some research by proxy on my way back to NJ, staying in Cooperstown, where Alice's mother was at school in the late 1920s.   The Knox School occupied the Otesaga hotel during the winter months, and then it turned back to being a hotel for the summer season.   It's in a spectacularly beautiful position, overlooking the lake (leaves just coming out look curiously autumnal in the evening sun), and is grandiose, with sweeping steps and an over-the-top elegant terrace.

And it was full of dressed up Young People, which meant that I had no difficulty whatsoever strolling in with a camera and, indeed, shooting away as though I were from the local paper.   Back at the somewhat more modest (thank goodness) hotel in which I'm staying, I asked what was going on, and th innkeeper said it was the Cotillion.   This, I thought, was a southern thing (obviously I'm quite wrong there) - whatever it is, it seemed to be something that I would deeply have loathed at the age of these girls / boys (who mostly seemed to be about 15 or 16).   Perhaps someone can fill me in on the social implications of this excruciating looking event?   It wasn't all that hard, though, to imagine that one could have had good parties there in 1928 or 1929, though - and imagine having this stunning lake as your View from School - other scenery would have a hard time in living up to it.