Been pondering this one for decades, and I'll tell you - the ". Landing strip". Theory never sat right with me, even as a younger man who wanted it to be true.
The practical problems are insurmountable. The lines are etched barely a few centimetres into the desert surface. No craft, ancient or otherwise, could use that as a runway without simply pushing the markings aside. Erich von Däniken did us no favours romanticising it beyond what the evidence supports.
What I find far more compelling is the ritual processional interpretation - that the Nazca people walked the lines as part of ceremony. Some researchers have linked them to water sources and mountain sight-lines, which makes considerable sense given how desperately arid that region is.
That said - and here's where it gets interesting for folk on this forum - the scale of the figures still demands explanation. The hummingbird, the spider, the astronaut figure. You cannot appreciate them from ground level. Someone needed an elevated perspective to design them with such precision.
Does that mean spacecraft? I'm genuinely uncertain. It might mean sophisticated surveying techniques we've underestimated, or it might mean something stranger.
What I'd push back against is dismissing the aerial-view question entirely just because the landing strip idea has been debunked. Those are two separate conversations.
What's everyone else's current thinking? Has anyone here looked seriously at the acoustic properties research - the idea that certain lines amplify sound during ceremonies? That thread feels underexplored to me.