The San Luis Valley Southern Railroad started as the San Luis Southern? Railway, chartered on 3-Jul-1909 to build a line south from the D&RG's standard gauge La Veta Pass line at Blanca, CO? to Taos, NM. Rails never made it that far, ending their southern progression at Jaroso, CO, just shy of the New Mexico border, on 3-Nov-1910.

The railroad became the San Luis Valley Southern Railroad as the result of a bankruptcy sale on 6-Jan-1928. For the sum of $44,500 and another $7284 in back tax liability, Colorado industrialist Charles Boettcher bought the railroad. Operations continued on an irregular basis until 1949, when customer base and physical plant had deteriorated so far that the railroad was put up for abandonment.

Abandonment was postponed several times, but when it finally seemed imminent, the Interstate Commerce Commission ordered the line sold at scrap value to anyone who would continue to operate the route. On 12-Dec-1953, the Southern San Luis Valley Railroad was formed to do just that. A year and a day later, it was reported to shareholders of the new SSLV that the ICC had come through with the approval for the purchase.

Within a few years, the SSLV realized that the far north end - near Blanca? - was the only profitable section of the railroad to operate. So, on 29-Apr-1957, the railroad petitioned the ICC to abandon the southernmost 29 miles, leaving only approximately two miles of track south of the Blanca interchange. Abandonment was granted and the line officially closed on 15-Mar-1958. 1959 brought the removal of another mile, leaving only 1.53 miles of operational track, serving a lettuce refrigeration facility and vegetable packing plant just west of the mainline at the far north end.

The SSLV lasted until 1994, when any sort of revenue operations came to a stop. The line was not abandoned, however, and in late 2007, it was reported that the remainder had been sold to the San Luis & Rio Grande, presumably to be used for car storage.