Railroad Network

The CTA Railroad Network is a representation of the North American railroad system that contains every railroad route in the US, Canada, and Mexico that has been active since 1993. It is intended for logical network programming, traffic analyses, and mapping applications. Corporate structure, a key to the simulation of routing, is explicitly temporal, allowing historical studies and comparisons. Supporting data on interlines and corporate ancestry allow the construction of routable networks for a specific target date. The network is an extension of the Federal Railroad Administration's strategic network.

The network is distributed in two versions:
  1. The raw version QN contains the full semantic content.
  2. The current version QC is an easier-to-use operational freight network that omits inactive lines and contains only current operators, but incorporates interlines as network links.
and in two formats:
  1. The official datasets are the ASCII "native format" files described in the documentation that will be most useful to programmers.
  2. Derivative shapefile versions are also available for the convenience of GIS system users. Shapefiles do not include interlines or milepoints, but do explicitly translate historic owner into the current corporate operator, attribute field W1. There are two separate layers for nodes and links, identified by a trailing "n" or "l" in the layer name.

Major differences from the documentation incorporated in edition 55 (2005 May):
  1. Virtually all active US lines have 100 m geographic accuracy.
  2. The subdivision field is now populated.
  3. Network files available in ESRI shapefile format.
Differences incorporated in edition 83 (2008):
  1. Mexican corporate structure and geography updated. (Source code ‘M’ objects in Canada and Mexico have alignments taken from the BTS NORTAD with approximately 1500 m accuracy.)
  2. Traffic densities have been transcribed from the FRA strategic network of 2005 for all US lines above 5 million gross tons/yr. (Classes: 1=below 5M tons, 2=10M, 3=20M, 4=40M, 5=60M, 6=100M, 7=above.)
Differences in edition 15 (2011 May):
  1. A 3-character LINEID field has been created to replace the former "Route." It resides in columns 37-39 of the ascii link file. The DV (Division) field has been dropped. LINEID typically identifies a route with a unique milepoint sequence used in a railroad's linear referencing scheme, but on occasion will be an arbitrary letter to distinguish different sequences within the same subdivision.
  2. The TKID field (Track number) has been expanded to 2 characters in columns 44-45.
Differences in the current edition 48 (2014 August):
  1. A new HEIGHT class of K is for lines that can accommodate autoracks but not doublestacks. A WEIGHT class of S is for cars in excess of 300,000 pounds. Additional undefined classes (eg, C and t) should be treated, for now, as unknown. (Height and weight limitations remain unknown on most lines.)
  2. Derived (not edited) variables EMLC and ENTRK have been added to shapefiles as numeric mainline class and number of tracks to facilitate variable map symbol sizes.

View documentation Description of the CTA Railroad Network (ASCII text 53 KB)   go

View maps which illustrate network features go

Download raw network QN48
  QN48R in native format (9.6 MB)   go QN48V in shapefile format (10.1 MB)   go

Download current operational network QC48
  QC48R in native format (5.5 MB)  go QC48V in shapefile format (7.4 MB) go

Download supporting data: Interlines, Railroad ancestry, Subdivision list (0.2 MB compressed)  go
     View railroad reporting marks and ancestry only, wconv.txt.

Supporting programs: RHA (reformats native ASCII files into GIS formats), RQCFS (constructs the operational network QC from raw network QN), Arc/Info loading macros.
     Download source and executables in a single zipped file (28 KB)

GIS details: Geographic accuracy is roughly equivalent to a scale of 1:100,000, but is object-specific (see documentation). Comparison to a set of 70,000 FRA inspection car GPS locations showed a lateral offset of 20 m root mean square, so a reasonable estimate of the geographic accuracy of active lines in CONUS would be 25 m RMS. The geographic coordinate system is decimal degrees, datum NAD27. No ESRI PRJ file is included with the shapefiles, but if there were, it would look like this (cut and paste if needed):


Several royalty-free shapefile viewers are available on the Web that you can use to make on-screen maps of this network. Possibilities include:
1. ESRI ArcExplorer
2. PCI Geomatics Geomatica
3. Quantum GIS
4. MapWindow

You will have to install the program and point it to the downloaded shapefiles on your computer.

Contact for questions and corrections: Bruce Peterson, 865-946-1352, PetersonBE@ornl.gov.



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