YOU CAN’T ACQUIRE CITY-OWNED PROPERTY BY ADVERSE POSSESSION, NO MATTER WHAT THE CITY PLANS TO DO WITH IT

That’s the outcome of the case reported on in a recent item on AZCentral, but that’s boring, so the reporter had to bring in all the extraneous facts.  If you want the straight (boring) legal analysis, read the memorandum decision of the Arizona Court of Appeals.  
It doesn’t matter how sympathetic the claim might be.  You can’t claim by adverse possession property in Arizona that’s owned by the state or a city.  
I have in past newsletters addressed both the subject of adverse possession generally, and the difficulty of claiming adverse possession against the government.