The St. Paul Subdivision or St. Paul Sub is an 30.9 miles (49.7 km) railway line running from Minneapolis

Minneapolis, Minnesota

Minneapolis , nicknamed "City of Lakes" and the "Mill City," is the county seat of Hennepin County, the largest city in the U.S. state of Minnesota, and the 48th largest in the United States...

 through neighboring Saint Paul, Minnesota

Saint Paul, Minnesota

Saint Paul is the capital and second-most populous city of the U.S. state of Minnesota. The city lies mostly on the east bank of the Mississippi River in the area surrounding its point of confluence with the Minnesota River, and adjoins Minneapolis, the state's largest city...

 and on into Saint Paul's southeastern suburbs along the Mississippi River

Mississippi River

The Mississippi River is the largest river system in North America. Flowing entirely in the United States, this river rises in western Minnesota and meanders slowly southwards for to the Mississippi River Delta at the Gulf of Mexico. With its many tributaries, the Mississippi's watershed drains...

. It is a segment of BNSF Railway

BNSF Railway

The BNSF Railway is a wholly owned subsidiary of Berkshire Hathaway Inc., and is headquartered in Fort Worth, Texas. It is one of seven North American Class I railroads and the second largest freight railroad network in North America, second only to the Union Pacific Railroad, its primary...

's Northern Transcon which runs from Chicago, Illinois to Seattle, Washington

Seattle, Washington

Seattle is the county seat of King County, Washington. With 608,660 residents as of the 2010 Census, Seattle is the largest city in the Northwestern United States. The Seattle metropolitan area of about 3.4 million inhabitants is the 15th largest metropolitan area in the country...

. Between Minneapolis and Saint Paul themselves, this route runs on former Northern Pacific Railway

Northern Pacific Railway

The Northern Pacific Railway was a railway that operated in the west along the Canadian border of the United States. Construction began in 1870 and the main line opened all the way from the Great Lakes to the Pacific when former president Ulysses S. Grant drove in the final "golden spike" in...

 trackage, and now forms the northern set of BNSF tracks running between the two cities. The companion route running slightly to the south is the Midway Subdivision

Midway Subdivision

The Midway Subdivision or Midway Sub is a railway line in Minneapolis and Saint Paul, Minnesota on the BNSF Railway's Northern Transcon which runs from Chicago, Illinois to Seattle, Washington. This is former Great Northern Railway trackage, and now forms the southern set of BNSF tracks running...

, though the St. Paul Subdivision is the busier set of tracks, hosting about 59 trains per day as of April 2009. It is the second-busiest rail line in the state, after the segment of the Staples Subdivision

Staples Subdivision

The Staples Subdivision or Staples Sub is a railway line running about from Dilworth to Fridley, Minnesota . It is operated by BNSF Railway as part of their Northern Transcon and contains the busiest segment of mainline track in the state, between Coon Rapids and Fridley...

 between Fridley

Fridley, Minnesota

As of the census of 2000, there were 27,449 people, 11,328 households, and 7,317 families residing in the city. The population density was 2,701.3 people per square mile . There were 11,504 housing units at an average density of 1,132.1 per square mile...

 and Coon Rapids

Coon Rapids, Minnesota

As of the census of 2000, there were 61,627 people, 22,578 households, and 16,572 families residing in the city. The population density was 2,718.1 people per square mile . There were 22,828 housing units at an average density of 1,007.2 per square mile...

.