I’m thinking to get to this page collection of images around the world that show the signs of mastery of stonework.
Megaliths.org has now great growing compilation of sites around the world:
and here is an album of pictures I had collected on my computer, taken from manymany places around the net.
Here´s video showing pictures of structures around the world, pointing the similarities and same techniques in building these ancient (knowledge about their timing is almost completely open) megalithic structures:
Megalithic Research, Eflatun Pinar, Turkey:
Russian -> English:
And more is coming.