From Westerlo, NY - a Helderberg Hilltown
- The Manuscripts and Special Collections unit of the New York State Library owns an extensive collection of land records covering the Rensselaerwyck Manor, an area that once included large portions of Albany and Rensselaer counties. The Rensselaerwyck Manor Papers at the NYS Library has a partial index of some of the tenants and the lots they leased. There is much more information available at the Library itself.
- Portion of map which is now the town of Westerlo and eastern third of what is now the town of Rensselaerville.
- Portion of map which is now the Town of Rensselaerville.