aabajian parent
If you want a real surreal experience, I suggest visiting Carlsbad Caverns, or a similar enormous cave system. I suspect the awe the author felt was the same sensation as being in an enclosure larger than any building. Think about being in an aircraft hanger then multiple the size by ten. There simply aren't any human-built structures as large. The sky becomes rock and it's just different than any place you've ever been.
Carlsbad is big, but there are bigger indoor spaces out there. Carlsbad's "big room" is 625 ft wide, and 255 ft high at its highest point. That is big, but things like stadiums get bigger. Carlsbad is long too (4km) but as a cave length isn't really perceptible. NASA's vehicle assembly building is 720 ft by 520 ft and 530 ft high, roughly the same but much higher than Carlsbad.
Tropical Islands Resort is a tropical water park (Germany): 690 feet wide and 351 feet high.
https://en.wikipedia.org/wiki/Tropical_Islands_Resort
https://en.wikipedia.org/wiki/File:Tropical_Islands_Halbe_14...
There are tours available for the largest building in the world (by volume) https://www.boeingfutureofflight.com/tour
The height is nothing much, but the main factory is 2,607 ft (794 m) along the longest dimension.