I want to not believe that I just spent 20 minutes googling around trying to find where one particular shot was done. Really, I do. But for now I will simply post a link to this pic, which confirms that the bit I was trying to figure out where it was is a turret on the outer wall, in front of the main keep of the castle, only shot with the round turret positioned in between the two large main towers, from a much lower angle than in the shot in the link.

And apparently there's a bit from ep. 1x13 shot at Raglan Castle in Wales. Which I still more or less don't know where it is. Uh, the castle, that is. Wales I'm pretty clear on at this point.

Just to prove it's not just me, there is, in fact, an LJ community dedicated to Merlin filming locations, merlinlocations. Location geeks, ahoy! And just to prove how "virtuous" I am, I am going to skip downloading the PDF of the pamphlet on the castle. Because I really should have been asleep 45 minutes ago and I think waiting another 15 minutes is likely unwise.