Pegasus Kingdom-Griffonstone Border

The Pegasus Kingdom-Griffonstone Border was a border marked by a river that divided the two realms. While the pegasus side seemed bare, the griffon side featured a small town called Beakwick, which was the site of the "genuine super storm" that was caused when the Weather Factory acted up.

Location and continuity
According to the Map of Equestria, the Griffons inhabited an entirely different continent than Equestria, which makes the location of the border questionable. In, it was revealed that the Griffons owned a large amount of Equestria, described as half of the land, extending to at least Canterlot, before they sold it to the ponies. This deal was so ancient that it was written in Olde Equestrianne, thus making it where it most likely pre-dated the current Kingdom of Equestria. Nonetheless, this means it was entirely possible that Griffon towns and cities dotted what is now modern day Equestria, meaning the border may have been in mainland Equestria.

Furthermore, it was also possible the town was located on the Griffon continent and Pegasi had colonies set up there. This may not be true however as it was said this was near Cloudsdale.

The nearest river to Cloudsdale was the Great Valley River, which was a massive river that connected all of Equestria.