The top 10 highest-grossing gambling cities worldwide, based on revenue generated from gambling activities, are:
1. Macau, China
2. Las Vegas, United States
3. Singapore, Singapore
4. Atlantic City, United States
5. Melbourne, Australia
6. London, United Kingdom
7. Monte Carlo, Monaco
8. Paradise Island and Nassau, Bahamas
9. Niagara Falls, Canada
10. Johannesburg, South Africa