The Oldest Dated Manhole in NY!
Central Park officially opened in 1860, but there was still much work going on, especially in the northern areas. A new reservoir, now named for Jackie Kennedy Onasiss, was being built to add to the Croton system. This manhole cover is a small souvenir of that time, and the earliest dated manhole cover in New York.
Although there were sewers, not to mention the first Croton Aqueduct, before 1861, there seem to be no surviving manhole covers from that time. It is not even clear if there were cast-iron covers, access points could have been covered with stone or even wooden lids.
The cast-iron architectural revolution was just taking off in New York in 1861 (Civil War notwithstanding), and the designs of the cast iron bridges of Central Park give some perspective on the design trends at the era. With no direct predecessors however, it is not clear from whence this design springs. Eighteen spokes? Fourteen cogs on the outer lid seating? Still it became the prototype of thousands of lids to come.
The engineers and designers were very concerned with the hydraulics of Central Park. This lid probably covers a settling well on a line of drainage pipe that carries overflow from the reservoir to the Pool and the Loch at 103rd Street. There is a diagram of the drainage plan (but not the manhole cover) in the 1861 Central Park annual report.
This treasure sits north of the Onassis reservoir and just east of the Central Park Tennis Center. This is about the level of 94th Street, and is quite selfie-accessible.