Softest Manhole Covers in NY!
In the playground at the foot of 96th St. in Riverside Park you can find two of the more unusual manhole covers in the city - covers covered in Astroturf. The two are located in a fairly recently renovated play field, and seem to be doing even better than most of the other turf, which is getting a bit dodgy.
There is a little color mismatch with the surrounding field, but maybe you don't want the manhole cover to completely disappear.
It is unclear what utility lies below, although the turf is a little but greener on these covers.
These two covers may be unique, but maybe others are even more seamlessly hidden.