Which are the largest frum communities in North America?
If I had to guess, and I’m probably leaving some big ones out, I’d say:
Brooklyn (Boro Park, Flatbush, Williamsburg, Crown Heights, etc.)
Monsey (including neighboring satellite frum towns)
Lakewood (including neighboring satellite frum towns)
Kiryas Yoel
Queens (Far Rockaway, Kew Garden Hills, etc.)
Chicago
Los Angeles
Toronto
New Square
Staten Island
Miami
Baltimore (Silver Spring, DC, etc.)
Cleveland
Montreal
Detroit (meaning Southfield, Oak Park)
Passaic (including Clifton)
In Europe I’d guess:
London
Manchester
Gateshead
Antwerp
Paris
Zurich
Elsewhere outside of Eretz Yisroel:
Melbourne
Mexico City
Johannesburg
Buenos Aires
Rio de Janeiro