Die Venus verfügt möglicherweise über einen unterirdischen Tunnel, der durch Vulkanausbrüche entstanden ist

Venus may have a lot of things that we will never know about.

I don’t think anyone with a little expertise in geophysics^* doubted that there were lava tubes on Venus, but theoretical certainty and actual evidence are very different things.

* and some awareness of what the Venus radar probes had already mapped.