A sign reads "No Trespassing," though it is evident that few heed the notice.
The Domes were built to facilitate the manufacturing of computers back in the late 70's early 80's but was never completed, evident from a couple of foundations that were started and left to molder. One of the buildings is shaped like a flying saucer and the other three are as if spheres were joined together, looking like huge concrete caterpillars.
Talk from the locals about the domes concerns ritualistic witchcraft and satanic worship. "Stay out of there and don't go into the tunnels" is the refrain, and indeed there are tunnels under the Eastern end of this facility. But despite all the stories whether anything more sinister than underage beer drinking, ghost stories, and the occasional squatter spending the night, has ever happened is unknown.
Nonetheless, staying out of the tunnels is probably advice wisely heeded.
Know Before You Go
Casa Grande, Interstate 8 Thorton exit, South 1 mile, East side of the road.