Yikes!
I've never seen one that I can remember with round elements, nor that big in diameter and spaced so far apart. It looks as unsafe to walk across with the wrong shoes, as to ride across.
I do remember a stage in the Vuelta de Bisbee where it seemed that several riders started cursing after going over a cattle guard with an elevated edge, and I thought "That's what you get for running 9 oz. Medaille d'Or rims"...
It seems they were from California, and complained that they had not been warned about the danger. OTOH, others from California complained about the warning given them regarding the off-camber first curve in a time trial around Saguaro National Monument, saying it made them lose time. Just a home-field advantage, I would say. I may have been prejudiced; it was long ago.
Now, I'm sure that there were and are plenty of nice, friendly cyclists from California, too.