"Jerusalem is like an Atlantis that sank into the seaA long, detailed article that explores both the full range of underground archaeological sites in Jerusalem and the political controversies surround the tunneling projects. It seems to make at least some effort to present all sides of those controversies.
everything there is submerged and sunken
This is not the heavenly Jerusalem but the one down below,
way down below. And from the sea floor they dredge up ruined walls
and fragments of faiths, like rust-covered vessels from sunken
prophecy ships. That's not rust, it's blood that has never dried"
(Yehuda Amichai, 1998)
Jerusalem has vastly expanded in the 7,000 years of its existence. Including, in the past two decades, downwards.
Beneath the Old City, one can already walk hundreds of meters underground, pray in subterranean spaces of worship and see shows in subterranean caverns and halls. There are plans in place to dramatically increase this area – essentially, restoring the true ancient city beneath the visible one. Jerusalem 2.0, below ground.
A handful of coins discovered inside a mikveh that had been blocked up ahead of building the Western Wall cast doubt on the story that King Herod built the walls of the Temple Mount. The coins were from the years 15 and 16 CE, about 20 years after Herod's death.This is true, but is presented in a misleading way. We already knew from Josephus that the Herodian Temple Platform was completed after the time of Herod the Great. This discovery confirmed what Josephus said. If it casts doubt on a story (and no primary sources are cited), it was a story we already had good reason to doubt. See here.
Reich and Shukron believe the inevitable conclusion is that it was heirs of the famous king, not himself, who completed the vast Temple Mount construction project.
There are many past PaleoJudaica posts on the underground tunnel excavations in Jerusalem. Some of them are here, here, here, here, here and links. There are also many past posts on the Elad nonprofit organization. See here and here and follow the links. Past posts on the Cave of Zedekiah are collected here. Cross-file under Temple Mount Watch.