The MKT railroad ran from Galveston, Texas and San Antonio, through Dallas and Fort Worth then north through Oklahoma. A big division point was at Parsons, Kansas, where the MKT split, one Division going directly north to Kansas City (via trackage rights on the BN) and even further north to Lincoln, Nebraska and Council Bluffs, Iowa (via trackage rights on the MP/UP).

Another MKT Division ran from Parsons to St. Louis, Missouri, crossing the Missouri River at Boonville, Missouri. This Northern Division ran on track just north of the river to St. Charles, Missouri. At St. Charles, the MKT track angled north to meet up with the old CB&Q line at Machens Junction. The MKT track ended at Machens, and the MKT trains continued over CB&Q/BN track to the terminal MKT yard at Baden, Missouri.

The northernmost portion of this Northern Division, from Sedalia to Baden Yard, was called the “St. Louis Subdivision”, and is the portion modeled on this layout.

A good historical overview of the MKT (although with a Texas emphasis) can be found here.

A little more about Franklin Yard

The tracks of the Missouri-Kansas-Texas Railroad were completed to Franklin in 1893. A roundhouse and shops were located in low, swampy, bottom land just southwest of New Franklin, known as Franklin Junction. In 1895, a two-story depot was built at this section and served as a division terminal office for twelve years. It was moved to a location closer to New Franklin on a string of flatbed cars and later burned.

In 1906, the Businessmen's Association of New Franklin acquired the land for the railroad to build a reservoir to supply water for the mighty steam engines. This secured the permanent division point for location at the Franklin Junction yards. The Katy Reservoir, as it became known, lies just to the north of the railroad yards at Franklin.

The expenditure of 15.5 million dollars by the Missouri-Kansas-Texas Railway in 1923 for improvements to the railroad yards, again assured the growth and continuation of the railroad division point location in Franklin Junction.

Construction of a forty-room hotel, a new powerhouse, an addition to the roundhouse and a new 90-foot turntable, were built by the Katy, along with machine stops, a new depot and office buildings. An immense oil tank 30 feet high and 114 feet in diameter with the capacity of 55,000 barrels of oil was erected to store oil for locomotives. Franklin became an important railroad center in 1923. Katy payroll was nearly a half-million dollars in 1930-31, with the New Franklin-Franklin area being the second largest of the companies in the state.

The beginning of WWII, 1939-1945, produced floods of rail tonnage and consequent year of prosperity for all railroads. Unfortunately, coal, chemicals and petroleum derivatives needed for treating the railroad ties were in short supply, as was good quality timber. Some twenty to twenty-five years later the wartime installation of inferior ties and the long stretches of fifty and ninety pound rails posed serious problems in the maintenance programs of the Katy as the postwar fortunes of the Katy deteriorated.

By the 1980s, it was evident the once undaunted, proud, thundering rails of the pioneering Katy were losing steam. The Katy was sold to the Union Pacific Railroad in 1986 and all her rails across Missouri lay abandoned and silent.

In the spring of 1990, the Missouri Department of Natural Resources transformed the 225 mile long rail beds into the Katy walking and bicycling Trail State Park, following the diverse and beautiful countryside of the once thundering rails known as the "Katy."