This clearing is where the first catstructs grew and were awoken, and is where future structlings will be grown. The dirt here is very soft and malleable, while just inches below is stone so hard that only the crystal claws of a catstruct may pierce it.
On cloudless nights, beneath a full moon, the runes on the surface stones glow and glitter. The catstructs like to come out from their cave on these nights to relax in the runes' soft, warm light, stargazing until they drift off to sleep.