We were having a discussion on another site about the use of molten aluminum poured into ant nests and after it hardens they dig up the nest so that ant freak professors experts can study how ants live … or something.
Anyway I remembered watching a video that is supposedly the largest ant colony ever dug up using this method, except they used a very liquified concrete instead of aluminum. It was in Brazil and the colony was YUGE.

How do subterranean cities of ants look like? 10 tons of cement were required to fill the holes and tunnels. Then it took weeks to uncover the secret megalopolis of the ants. With the help of mechanical diggers, Brazilian scientists removed tons of earth. At last, the scientists begin to see the structure of the city state.

The video is a little over 3 minutes.

https://www.youtube.com/watch?v=dECE7285GxU