Currently owned by the Spellman family and on the market for $3.1 million. NLT, with support from Peconic Land Trust, is working to finalize the acquisition of the Spellman parcel using the Community Preservation Fund and private donors. Funding for transaction costs is being sought through the Land Trust Alliance (LTA) and NLT is actively working to privately raise $600,000 for closing costs, demolition and ongoing land stewardship.

This 30-acre parcel is currently on the market for $30 million. It is culturally significant not only because of known unmarked burials in the 15-acre vacant parcel, but also because the palatial mansion located on the parcel was designed by Grosvener Atterbury, a prominent and influential American architect, urban planner, and inventor, celebrated for his innovative designs and contributions to modern architectural. The grounds of the Atterbury mansion were also designed by Frederick Law Olmsted Sr., known as the father of American landscape architecture. NLT is collaborating with the Preservation League of New York to nominate the property, known as the Atterbury Estate, for Seven to Save, which could open additional funding opportunities. NLT has the ability to steward the Estate and use Community Preservation Fund money for 80-95% of the acquisition costs. The home will become the homebase for educational programming for NLT.

The Sillerman Property, located at 7 Southway Drive in Southampton, NY, sits adjacent to the culturally and ecologically significant Sugar Loaf property. NLT is actively working to acquire this approximately 15-acre parcel from the Peconic Land Trust (PLT) to help establish a contiguous protected area. This acquisition was made possible through a $10 million loan from a private benefactor, which is being repaid through the sale of development rights to the Town of Southampton. In accordance with Community Preservation Fund requirements, the mansion on the property must also be demolished.

The Sillerman parcel is currently held by PLT and is slated for transfer to NLT as a form of reparation for historical land dispossession. Restoration efforts on the Sillerman property include removing invasive species, excavating root masses by hand, backfilling holes with soil, stabilizing larger areas with biodegradable jute erosion cloth, and sowing native grasses and forbs. The Sillerman site, recently appraised at $12.2 million, contains two existing structures.

The contiguous properties of Sugar Loaf and Sillerman hold immense cultural and ecological significance as a Shinnecock and neighboring tribal burial site dating back over 3,000 years. Restoration efforts have focused on establishing a native plant meadow within the footprint of a demolished estate. The area is part of the rare and ecologically critical Shinnecock Hills maritime grassland. Creating this contiguous protected area that includes the Sillerman property is essential for managing the broader landscape. It enables coordinated efforts to control invasive species, implement erosion control, and restore native ecological communities such as the critically imperiled maritime grassland and shrubland. This larger, connected preserve will enhance biodiversity and support key ecological processes like soil stabilization, water filtration, and carbon sequestration, while also protecting culturally sacred land from ongoing threats of overdevelopment that endanger both ecological integrity and Indigenous heritage.