In the first Kanon Promotional Video that was released there's 2 locations that was not shown in the show itself. This PV is included on the teaser DVD Kanon Prelude that was released in Japan. These locations are close to the tram stop Yamahanakujō Station in Sapporo.
Image from PV1 - 00m33s
This pet shop is called Ria Pet Shop in real life.
Image from PV1 - 00m14s
The church in the background is no longer there, but other than that it's a pretty good match. On the left is a 7-Eleven store.
Image from Episode 8 - 11m59s
On the other side of the 7-Eleven store is this place that was shown in the show. I've marked the path from the pet shop to the 7-Eleven in the map below.
This location was visited on 2015/10/29.
Special thanks to the ones who went here before: