The New Amsterdam Pastiche Regatta is an afternoon aboard rented rowboats on Central Park Lake, with attendees dressing and acting as if at a fancy regatta (e.g. The Henley Royal Regatta)
Or preferably their exaggerated and embellished interpretations thereof.
There will be (mock) contests of rowing and diplomacy similar in concept to the Idiotarod--albeit diametrically opposite in form and style. But mostly if there is any contest worth winning it will be of aesthetics, and portable culinary arts (picnicking on the boats.) Participants should bring some manner of haute comestibles to share with others.