What ? And you weren't "arrested" ? Shame on you ! Now go do the right thing, and ask a bunch of people in city hall there "Can I ?" and "Does this need a permit ?". Be sure to have a shovel in your hand while you're asking them, so they can understand the full implications of your question.
Hurry , go do the right thing and swat those hornet's nests. So that you too can fret yourelf silly . When , in fact, as you're experience shows, no one really gave a moment of thought.
Just avoid obvious historic monuments, and busy-bodies, and .... presto, no one cares.