How green was my anthill

These small tumps, humps, hummocks or hillocks made by  yellow meadow ants glow green like traffic lights signalling the first stirrings of spring. They provide useful prominences for birds to perch, rabbits to check their surroundings and foxes to deposit faecal messages. Mosses relish the dry soil and the passage of air offered by the elevation. I like to think of the ant colony beneath, dormant or maybe rousing as the days lengthen and the queen begins to lay eggs again.

As far as I'm aware there's not much knowledge of what lies within or below these anthills.  Yellow meadow ants are tiny but give a painful bite.
 In other parts of the world (fire) ant nests have been cast in aluminium and you can see the astonishing result here.