[Fury]

As far as I know, only Yorkshire has "ridings," and despite their seeming each to be about as much as an old circuit preacher could have covered with a horse, the philologists tell us that they are just a cutting up into THIRDS, in Old English, THRIDINGS, and the "th" ceased to be pronounced, and eventually, ceased to be written.

This seems reasonable. The word seems to be used in other areas of Canada, perhaps by some older folks?

[laconic]

I remember a few years ago, while watching a CBC broadcast on the Canadian parliamentary elections, that they referred to the member districts in Canada as "ridings".

[Canadian Outrage]

Well you just taught me something. Sounds reasonable to me also.