Fishing in or near cities and populated areas can be quite difficult. The simple reason is that there are just not enough fish around. Because of the high population density many popular spots near cities are just overfished. In order to catch fish near a city it is essential to know good spots that hold fish.
Just as important is the type of bait and the bait presentation. City fish are cautious and wont take anything. Only bait that is fresh and presented in a irresistable way has a chance to be taken. Also berley would be highly recommended to draw the few fish to your spot.

I have fished around cities and only really had notable success when drifting on a boat near reefs that were a bit further out from the harbor.
While watching fishermen on wharfs and rocks around the city, I never saw anyone catching anything, except some small bait fish.
From my experience people fishing in cities need an enormous amount of patience and skill to score a fish in the crowds.
It might be easier to fish in city park lakes that are frequently stocked up with fish - I have never tried that.

Because of frequent boat traffic, noise, lights and temperature differences the bite behaviour and bite times might differ from normal fishing times.
Although whenever I fish near a city, I still get most strikes (if any) during the major times. I tried to fish from wharfs at night time to avoid the crowds and had a few bites then.


But in summary there are a few things to increase the chances to catch fish near cities

use only the best bait - preferably freshly caught bait present the bait in a nice way - make it look good use berley to draw fish to your spot choose the right time - use fishingreminder to find good times to go fishing look where other people fish and observe if anyone catches anything bring a lot of time and patience be prepared to go home without a catch or even without a bite. know the season and read local fishing reports to check if fish are around find someone who caught a fish in the area and ask for advise Read the interesting book "City Fishing " by Jerry Dennis

 
If anyone has more tips or different experiences, please add a comment.