Living in the foothills a while ago we had a similar issue with baseball practice on mailboxes. Kids would smash mailboxes from their posts
We fixed that after a few methods failed. Put the original mailbox inside of a new larger mailbox then filled the gap around it with concrete
Few days later neighbor near the mailboxes heard a nice THUDDDDDD and cursing
Problem seemed to go away immediately after that.

We fixed that after a few methods failed. Put the original mailbox inside of a new larger mailbox then filled the gap around it with concrete




Back when I was young (25+ years ago), my friend decided to hit a mailbox with a rental car he was driving... We (the passengers) had no idea what he was doing. We weren't drinking, but were out do nothing constructive late one night... anyway, He drove on the side of the rode, but just missed this mailbox...
So he drove around for a while (really windy roads/hilly area, similar to El Dorado Hills)... he came back up the same street, but this time he made sure to hit the mailbox by driving even further off the rode...
Of course, ivy concealed a stack of bricks (cemented together) at the base of the box and post...
Boom!... Ended up bending wheel, led to a flat tire, car needed an alignment, and broke the passenger-side mirror off the car door, broke the headlight and scraped up the side of the fender...
Really upset our other friend, who worked at the rental car agency and had let the other guy borrow the car (too young to rent, about 18 or 19)...
Ah, the stupidity of youth...