Hi Jon,

Ok, not an attack from me, no worry. I am in line with catastrophist ideas, and totally open to the possibility of very early alien explorations on earth (science fiction amateur too). Giant "human" footprints with dinosaurs ones is a fact, and there are many examples of OOParts (Worlds before our own, Brad Steiger).
My point was that Malta cart ruts do not seem to belong to this category, for the geological reasons I exposed (my opinion only, not being a geologist).
Let me add another comment to clarify my view:
This does not rule out the possibility that these "cart ruts" in Malta could be very old. Sometimes they run underwater and suddenly end on sheer cliffs brinks. And the cliffs look much younger than ruts.
The under water tracks are all on north east coast, whereas many tracks interruptions are on south-west cliffs, which suggests a tipping of the islands plateau, as a whole, and a catastrophic creation of the cliffs, as I said looking young and very high (130 m at Ta Cenc, in Gozo).
There, I could note that ruts run close to geometric marks on artificially leveled rocky ground, all very worn out, and very close to cliffs brink. Who would create quarries, monuments and roads so close to such cliffs?