The Jupiter and Lake Worth Railroad, or the "Celestial Railroad", was a short narrow-gauge line that was built along the eastern coast of Florida between its namesake towns. Construction of the 3-foot gauge line began in 1888, and freight/passenger operations commenced the following year.
It was called the "Celestial Railroad" due to fictional stops named "Mars" and "Venus" (along with the line's terminus at Jupiter).
In 1894, the Jacksonville, St. Augustine and Indian River Railroad built a parallel line approximately 1.5 miles west of the Celestial Railroad; this Henry Flagler property slowly garnered traffic away from the Celestial Railroad, which forced the small line into abandonment in 1895, a mere 6 years after it first turned a wheel. The railbed remained, however, along with some of its infrastructure; rails remained in place until the 1930s, and wooden ties were left to nature (one tie was found along the former right-of-way as late as 1998, and was donated to the town of Juno Beach).
Today, surprisingly, over 100 years after the line's abandonment, the flat grading of the former right-of-way can still be seen in the northeast corner of Juno Dunes Natural Area, if one knows where to find it.
The book at the link below describes a detailed tracing of the Celestial Railroad in 1982; the article starts on page 5 and runs to page 22.