I always thought the numbering plan was devised for the International Map of the World, which is referred to by the cited NTS Wikipedia page. Saludos, Todd Minsk <mailto:[log in to unmask]> [log in to unmask] Hanover, NH USA From: Maps-L: Map Librarians, etc. <[log in to unmask]> On Behalf Of Mike Flannigan Sent: Thursday, June 18, 2020 08:33 To: [log in to unmask] Subject: Re: 52 K/5 Designation on Canada topographic maps Thank you all. Thanks to your help I will call it the NTS code for now. Roger Wheate supplied some links that describe the system. Here is a pretty good explanation: https://en.wikipedia.org/wiki/National_Topographic_System Mike On 6/17/20 6:57 PM, MAPS-L automatic digest system wrote: Hi Mike, I think what you're looking for is the Canadian National Topographic System (NTS) grid, which sections Canada according to those alpha-numeric designations. https://www.nrcan.gc.ca/earth-sciences/geography/topographic-information/maps/national-topographic-system-maps/9767 +Evan Evan Thornberry GIS Librarian University of British Columbia Library [log in to unmask] <mailto:[log in to unmask]> On 2020-06-17, 9:01 AM, "Maps-L: Map Librarians, etc. on behalf of Mike Flannigan" <mailto:[log in to unmask]@ATT.NET> <[log in to unmask] on behalf of [log in to unmask]> wrote: I have a question about Canada topographic map designations. Oak Lake (1:164.042 scale) in CN has a designation of 52 K/5 or 52K05. I want to know what that designation is called. I think it is not the Military Grid Reference System (MGRS), but military people use that designation whatever it is called. Mike