The southeast corner of Central Park park is dominated by a pond called The Pond and behind it, if you’re coming in from the east, the Hallett Nature Sanctuary.
From the Central Park Conservancy’s website:
Hallett Nature Sanctuary is one of the Park’s three woodlands (along with the Ramble and North Woods). It was originally called “the Promontory” by the Park’s designers. The underused and inaccessible landscape was closed to the public and preserved as a bird sanctuary by NYC Parks Commissioner Robert Moses in 1934, and in 1986 renamed in memory of George Hervey Hallett Jr., a birdwatcher, naturalist, and civic leader.”
In May of 2016, the sanctuary re-opened after more than 80 years.