A Crossing of the Texas & Pacific Railway and the St. Louis Southwestern Railroad
In 1873, the Texas & Pacific (T&P) Railway built west across northeast Texas from Marshall to Dallas. A few years later, the Tyler Tap Railroad was organized to "tap" the T&P main line at a location near Big Sandy Creek. This would provide the citizens of the thriving town of Tyler with rail service over a 21-mile narrow gauge line. Because the lines were of different gauge, there was no direct connection. Instead, the Tyler Tap paralleled a T&P siding for some distance, providing a means of exchanging cargo with the T&P. In 1880, under the new ownership of the Texas & St. Louis Railway, the Tyler Tap was extended northward, crossing the T&P line and proceeding to Texarkana via Mount Pleasant. In 1886, this line was converted to standard gauge and rail connections with the T&P were established at the crossing, which became known as Big Sandy Switch. The Texas & St. Louis Railway eventually became part of the St. Louis Southwestern Railroad, nicknamed the "Cotton Belt" for its extensive network in the cotton growing regions of Texas and Arkansas.
Railroad Commission records indicate that an electric interlocker, numbered 137, was established at Big Sandy in 1928. This late date is somewhat surprising; the laws regulating interlockers were passed at the turn of the century and most major rail crossings had been upgraded to meet the interlocking requirements within a few years thereafter. It is apparent that extensive traffic on both lines was common for the entire history of this crossing. Since a union depot was built at the crossing, it is likely that interlocker controls were remoted there in lieu of a manned tower. Today, both lines are operated by Union Pacific which sends dozens of trains daily across the diamond at Big Sandy.