Through people who have visited Col. Moammar Gadhafi's Bab al-Aziziya compound in Tripoli talked about the miles of hallways and bunkers built below ground, no images had ever been seen of them.
As Mark noted earlier, now that the rebels control the complex it is being explored and ransacked. And today, we got images of those legendary tunnels. In this Al Jazeera report, you'll see video of one of those tunnels at around the 1:25 mark:
The Al Jazeera correspondent says that inside the tunnels rebels found gas masks and food. AP photos and BBC reports showed a room with a bank of telephones. All of the rooms are air-conditioned and the network is so extensive, reports Al Jazeera, that "where it all leads, no one knows."
The BBC reported during its coverage that they had spoken to an Italian plastic surgeon who had been to the compound and said he saw an underground operating theater and a hospital ward.
In 1984, concerned about the threat to his regime from an increasingly hostile West, Gaddafi ordered the construction of thousands of miles of what were described as 'irrigation tunnels'.
The project, which cost a staggering £15 billion was titled the Great Man Made River and promised to bring water from the Saharan aquifer in the south of the country to the major cities of Tripoli and Benghazi.
But built from 75 ton sections of reinforced concrete that are laid as deep as 600ft in places, the 13ft tunnels also provide a handy way of avoiding detection and hostile attack.
We would take that reference to "thousands of miles" with a grain of salt. As the rebels have more time to explore, we'll know more about just how extensive the tunnels are.