This extension to the Port Jefferson branch of the Long Island Railroad was built in 1895. Station stops were made in Miller('s) Place and Rocky Point, and the line terminated in Wading River at Wading River Manor Road.
It was along this rail route that Nikola Tesla decided to build his Wardenclyffe laboratory, in Shoreham. It remains as his lone surviving laboratory today.
The extension was abandoned in 1939; none of the stations still stand.
Thanks to Kevin F. Story for contributing information about this route.