Trains!

From Saint Louis County Park's Museum of Transportation:

The Missouri, Kansas, & Texas Railroad - better known as "The Katy."  First railroad to enter Texas from the north, the Katy was in operation from 1870 to 1988.

Great Northern Railway - service from Saint Paul, Minnesota to Seattle, Washington, c. 1890-1970.

Atchison, Topeka, and Santa Fe Railway (can you hear the song?).  In operation from 1859 to 1996 when it merged with the Burlington Northern Railroad to form BNSF (Burlington Northern and Santa Fe).

The Chicago, Burlington, and Quincy Railroad, also known as the Burlington - service across the Midwestern U.S. and the near western states; main connections in Chicago, Minneapolis-St. Paul, Kansas City, Saint Louis, and Denver.  In operation from 1849 to 1970 when it merged with competing railroads to form the previously mentioned Burlington Northern Railroad.

Union Pacific - service from Chicago to New Orleans and all points west since 1862 - our nation's largest railroad network.

The Missouri Pacific Railroad - one of the first railroads west of the Mississippi River.  Originally organized in Saint Louis in 1851as the Pacific Railroad, renamed Missouri Pacific Railways in 1872, and finally Missouri Pacific Railroad in 1917.  "MoPac" merged with Union Pacific in 1982.

Joplin-Pittsburg Railroad Company.

New York Central Railroad - operated in the Northeast and Midwest from 1831 to 1968 when it merged with competitor Pennsylvania Railroad to create the Penn Central, which was eventually absorbed by CSX.

The Milwaukee Road, officially known as the Chicago, Milwaukee, St. Paul and Pacific Railroad, operated from 1847 to 1986.

Missouri Pacific's iconic "Screaming Eagle."

Alton and Southern Railway, in operation since 1910.  It is now a subsidiary of Union Pacific.

Originally the Pawnee Railroad (1888), the Chicago & Illinois Midland Railway in 1905 (but it never went to Chicago!), then the Illinois and Midland Railway since 1996.