Series consists of maps, plans, profiles and index cards providing information on Canadian National Railways' property and right of way in Ontario, and some adjacent areas. The documents were either prepared in or accumulated by Central Region offices in Toronto. Many were prepared by staff surveyors or engineers (C.N.R. Land Surveys Office or predecessor companies offices), others were obtained from local land registry offices or private surveyors-engineers offices
The period covered extends from 1853, decades before the creation of C.N.R., to the years surrounding the company's privatization in 1995, thereby covering the creation of local independent lines, their absorption into larger companies, such as the Grand Trunk Railway, Canadian Northern Ontario Railway or Canadian Northern Railway, to name but a few, themselves eventually brought under the umbrella of the Canadian National Railways at the time of the First World war, when war and over expansion had led to serious financial difficulties.
The collection of plans offers a glimpse of the expansion and general extent of the network and its subsequent gradual reduction, a process undertaken very shortly after the amalgamation. The plans offer information on location of the lines but may also document transformations brought to the right of way, original names of land owners, dates of abandonment of lines, names of purchasers. Interesting in their own right, these plans they supplement information already available at LAC in the Canadian National Railways Fonds.
It must be understood that the series was not transferred complete to LAC. (A preliminary list which accompanied the transfer showed that the collection was already lacking hundreds of potential numbers and, from those actually listed, hundreds were not found in the eventual transfer). Obviously, in the course of its operational life, the series underwent transformations and obsolete plans were disposed of.
The transferred documents were submitted to a further selection process in order to reach a balance between completedness, efficient use of limited storage facilities and potential research value of documents.
The following criteria were applied. LAC removed exact duplicates, near exact duplicates, several incomplete, unidentifiable or very heavily damaged documents, plans which presented a limited interest (without measurements or bearings), several plans of level crossings where accidents occurred (CTC preserves complete files on the subject), or minor plans for already very-well covered areas, especially in the Toronto, London, Windsor or Hamilton industrial areas).
Loss of information is minimized by the fact that local land registry offices also document land transactions (in fact many plans of this acquisition originate from such offices), and by the fact that many plans were digitized by CN in the 1990's (though the fate of the files is unknown), and that C.N. HQ Montreal is believed to hold a microfilm copy of plans created by regional offices (fate of these plans is also unknown, recent rationalization and move of records in Montreal has led to the disposal (destruction) of a yet unknown amount of records, including many maps and plans).
Most of the plans with an early date are actually annotated later copies of originals. This series of maps was active to the end. Very early records could be modified/annotated at will. Some of the earlier records seem to have been copied and probably destroyed (the sole surviving version of the original map being a recent copy).
Sizes vary tremendously from the rare 15cm by 20 cm document to the 60cm x 2500 cm roll.
Some rolls contained multiple plans. For conservation purposes these were separated and a new tag was created and attached. This tag contains the original tag number plus a distinguishing note (plan 1, plan 2, plan 3, etc.) for better identification in the finding aid.