This is an easy multi set for the purpose of checking the accuracy of your GPS. It was set specifically for the Geo Jamboree and was verified by surveyors using high quality GPS surveying equipment.
You will be looking for a concrete monument set flush with the ground whose true coordinates are N.41°25.53353 W.73°12.57067 WGS84 with an altitude of 204.8 feet NAVD88 Geoid 2003
To get to the second stage REPLACE the last two digits of the published coordinates with those found stamped into the monument face. (North on top, W under)