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.