A physical building where documents relating to land are filed and stored (and other documents as well). Historically these were secure fireproof buildings ensuring the availability of records to verify land ownership, e.g. loss of deed papers by an owner. Ontario land registry offices are sequentially numbered from 1 to 66. For modern plans recorded in the registry office, the two numbers before the alphanumeric identify the originating office, e.g. 66R-12345 reference plan from Toronto; 43M-1234 subdivision plan in Peel.