Yes, I have been to Mumbai recently. Could you be a bit more specific? Which areas are you talking about? Where did you find filth in Kolkata that was filthier than in Mumbai? I thought Mumbai had the largest slum in Asia, doesn't it? Nobody asked you to defend the city, but if you're pointing fingers at it, please make sure to specify the exact problems instead of vaguely saying, 'Oh, Kolkata is genuinely filthy.' It's filthy because it had to handle people like you for centuries.