East St. Louis is not part of St. Louis. It’s not even part of the same state.
Louisville, KY is another city where the east side of town is considered ritzier.
Here in Cincinnati, several neighborhoods that surround downtown are considered the crappiest. The “worst” are Over-The-Rhine and Avondale just north of downtown, and Price Hill, to the west. Frankly, they are much safer than the neighborhood just south of downtown. You will die if you try and walk there.
It’s the Ohio River.
I came here to say this as well. East Memphis= rich people (for Memphis).
East San Jose is the worst part of town. Same for East Palo Alto (which is actually its own city and not part of Palo Alto).
The eastern and northern parts of Montreal are generally the poorer areas. These sectors used to be industrial, but when the factories closed employment dried up. The prevailing winds are to the east, as is the Saint Lawrence River’s current, which might be why factories were put there in the first place.
The seaside of a town would also be home to the docks and associated neighborhoods, though, which are not generally your toniest areas.
For what it’s worth, south Dallas is considered the bad part of town around here…if you can figure out which part of the metroplex actually counts as “south Dallas”.