Under ATSF ownership, the GC&SF was extended northwards via Fort Worth to Purcell, Oklahoma, northeast via Dallas to Paris, Texas, southwest to San Angelo, and northwest to Sweetwater, where it connected to the Panhandle and Santa Fe Railway, the major ATSF operating subsidiary serving Lubbock and the Texas panhandle.

Acquisitions and extensions of the GC&SF into East Texas would reach Beaumont, Longview, Port Bolivar, and Oakdale, Louisiana.

The Gulf, Colorado & Santa Fe Railroad (GC&SF) was chartered, and the state agreed to grant 16 sections of land per mile of track laid.

The plans to initiate construction were formulated by the railroad's first engineer, General Braxton Bragg, former commander of the Confederate Army of Tennessee.

At other meetings in 1875, the board of directors asked for proposals for contracting the building of the bridge across Galveston Bay and for the laying of track to Arcola, Texas.

On April 30, 1875, Henry Rosenberg, president of the GC&SF, signed a contract with Burnett and Kilpatrick that included the construction of a bridge across the bay, complete with a lifting draw, for $69,000.

In September 1876, the Galveston, Houston, & Henderson Railroad completed a new passenger depot, located on the corner of Avenue A and Tremont Street.

The company planned to cross the Brazos River and proceed to Richmond, where it would connect with the San Antonio line.

By the next year, the company also completed an iron bridge 480 feet long over the Brazos River, and by October, a regular train was being run over the road.

Directors voted to advertise for a loan of $250,000 for 90 days, which would enable them to pay off the debts and finish the road to Richmond.

GC&SF authorized a daily whiskey ration, and Sherman dispensed a dipper of liquor at the end of the day to each member of the crew in an effort to keep morale high.

William Barstow Strong, president of AT&SF, actively pursued a way to break Gould's stronghold on Texas railroad commerce.

Plagued by additional financial problems, Sealy and the other leaders of GC&SF realized the railway would need a connection north out of Texas if it were to survive.

In 1904, the board granted Goedhart and Bates a five-year lease to a strip of land on the east end of the Gulf Company in Galveston, which would be used for canal purposes in connection with the grade-raising of the city.

Construction of a 98-mile branch line from Lometa through San Saba and Brady to Eden was commenced in 1910 and completed by the end of the following year.

Their plans were for an eight-story fireproof building made of steel-reinforced concrete and faced with white enameled brick.

In 1937, AT&SF purchased the Fort Worth & Rio Grande Railway from SLSF and immediately leased it to GC&SF, thus gaining a valuable and shorter route to Fort Worth from the west and from the livestock-raising areas of the Edwards Plateau than the previous routing via Temple.

In one such instance AT&SF agreed to work with the Duval Corporation to develop a sulfur mine at Rustler Springs, Texas.

AT&SF built a 30-mile branch line and conceived the ingenious idea of transporting the sulfur in a molten state from the mine to Galveston, where it would then be shipped by sea.