According to the Sanctuary’s brochure:

The Putnam and Dutchess Railroad had planned to split from the New York and Boston Railroad in Carmel and pass through this site. In 1873 it reorganized as the New York, Boston and Montreal Railway. However, the Panic of 1873 hit and the leases and mergers were cancelled. Construction on the Putnam and Dutchess Railroad stopped and the intended route was never completed leaving the railroad abutment abandoned in the woods.