Question- Terror Tower, was the location filmed in London?

I doubt they had the budget to film just one episode in London. And if you look at the architecture of the building in the episode, it doesn't match Tower of London. TOL has no red shading on the top, and four towers on each side of the building. The one in Terror tower has that red shading.

And I'm pretty sure it was filmed at Casa Loma in Toronto. Which is also being used for the upcoming Goosebumps movie.

https://www.google.com/search?q=casa+loma+toronto&biw=1366&bih=653&source=lnms&tbm=isch&sa=X&ved=0CAcQ_AUoAmoVChMIgvzRh4SvxwIVh4YNCh1iTgD-#imgrc=_

No it was filmed in Casa Loma which is a tower which is an tourist attraction in Toronto

As others have said, it was not filmed at "Ye Towers of Julius, London's lasting shame, with many a foul and midnight murder fed".

https://en.wikipedia.org/wiki/Tower_of_London#/media/File:Tower_of_London_(Foto_Hilarmont).jpg

I forget whether they said it was the Tower of London in the episode. I assumed it was some fictional other castle in London, "the other Tower of London".

As others have said, "Terror Tower" was filmed at Casa Loma in Toronto, Canada, which looks a lot more like the castle in the episode.

https://en.wikipedia.org/wiki/Casa_Loma#/media/File:Casa_Loma.JPG