Fordow is dramatically different from Natanz, where the Iranians constructed an underground structure and then buried it.
All of the construction at Fordow, as seen in Landsat 7 images, was underground. And it was very, very deep.
Hence why the US engineer the GBU-57.
How did we get from a bit of remote land in rural Iran to the US bombing what's now the Natanz Nuclear Facility?
Construction began in April 2000.
Imagery from the since decommissioned Landsat 7 shows us the construction of the project over time.