Reversionary land.

The 1984 Report of the Auditor General of Canada, Section 6.90.

 House of Commons Ottawa April 29, 1974 Mr. Hamilton (Qu'Appelle-Moose Mountain) Progressive Conservative: "Has the Minister a legal opinion from the Department of Justice as to their ownership of land underneath the rails? I put my question another way by saying that the Charter of the CPR and under the Charter of the various railways that make up the CNR, this land belonged to the Crown and was granted to the railways for the sole purpose of transportation. When any railway gives up land and no longer uses it for the purpose for which that Charter was granted, all that land reverts to the Crown which was the grantee."