Most of the stains and rust had been wiped off the wall, revealing a map of the Shelter's interior before the two of them.
Although parts were damaged or peeling, it did not affect their overall view.
The Shelter had twelve levels in total and an extremely complex interior, with eight levels underwater and four above, divided into administrative, daily living, residential, production, medical, and other areas.
There was even a tall tower in the middle, with an internal elevator leading straight to the top.
Different clearance levels only allowed access to corresponding areas, under strict control.
Judging by the size of the living quarters and the number of rooms, this shelter might have housed fifty thousand or even a hundred thousand people at its peak.
So the Shelter was even larger and more complex than Yang Yi had imagined.
Its underwater portion was larger than the part above the surface!
Exploring every part of such a complex shelter thoroughly would take at least two or three weeks.
Besides, many places had probably been emptied out, so going there would be a waste of time.
Yang Yi did not intend to explore everything. He planned to visit the most remote restricted areas requiring the highest clearance, where important items or clues and information were far more likely to remain.
One was the General Warehouse at the very bottom, the place most likely to have supplies left. It occupied underground levels four through eight at the intersection of the cross, with all five levels opened up for use as a warehouse.
The other was the top of the central tower, where the Shelter's captain's room was located. It required extremely high clearance and might contain information or clues.
Yang Yi told Su Na his plan. She nodded in agreement, holding a