I'm still wondering about the secret tunnel in the Great Pyramid of Giza with double false door that was found with a robot. They never further researched what's on the other side of the second false door.

Also it is known based on radar screenings there are some empty spaces under the Sphinx, quite likely very ancient chambers. I wish they would dig bellow the Sphinx to find out what's actually there.

I guess it would cost a lot of money and be time consuming and risky so they won't do it (in both cases). Pity that we might not know what may be there.