In the South, the ants excavate right through the concrete sidewalks.
In New York City, roaches are a HUGE problem and rats are a HUGE problem. You can see rats racing around at dusk behind buildings or in the subway when it's quiet. Or near garbage piles. In the summer, the worst thing is the smell of a humid city street-- a lovely amalgamation of vomit, urine, maggots, rotting trash bags, all baking in the sun.
In fact, one of the worst streets was W 43rd across the street from the NY Times building....