I see the holes Elric, but they're not in a place that previous system X castles have had holes. That does beg the question, what
are they there for?
Richard's close-ups convince me even more that this is a Clip system castle, like the Spanish lighthouse. It's suprisingly badly connected with gaps visible between the pieces. I wonder if they did that so they could easily take it apart again?
I also notice the tower tops are no longer one piece like the System X tower tops, there are gaps visible there too.
Nota also that the Clip system can still sometimes incorporate System X connections, e.g. to hold the torch brackets in place, but the main connections between large pieces have changed.
I like the shapes of these castles, and I think it would be possible to expand and modify them, but it's going to require yet more pieces of clip system castle to do it. I really wish they'd done these in System X (or better, Steck) as I have plenty of spare System X I could have used to extend straight sections, and the new angled corners.
It's a shame they never managed a full round tower in System X. Round towers have been popular for centuries, as they're stronger against undermining and wall-busting missiles.
Here's the keep of Rochester Castle in SE England. One corner was undermined and toppled during a siege by King John (he of the Magna Carta), by digging a tunnel propped up with timbers. They then stuffed the tunnel full of dead pigs and set them on fire. As the pigs burnt (nice and fatty) they burnt out the props, and hey presto, toppling tower.
When the keep was repaired they rebuilt the toppled towers round!