The Puerto Rican meter gage system was known as
"American Railroad of Porto Rico". (Spelled correctly) Back in the late 70's there was a very interesting museum in Fajardo, PR which included several sugar cane cars, an open coach, and a really beautiful Glover loco. The Glover has since been sold off island, and the museum no longer exists.
The system completely circled the island which is about 100 miles long. It's main purpose was of course to handle cane from field to mill, but at one time there was passenger service.
Many coastal towns still have remnants of trackage, particularlt wharfs and docks. In addition, there are bits of track scattered here and there, but not much.
I just wish I had been down there a few years earlier, sinc it must have been pretty interesting.