How to set up multiple occurences of same event with RNG?
I think you will need to create new event entities for each city, add a location field (Address?) and a date field, so your users can tell the difference. You will need to make the discovery layer before the event pages show a clear difference between your events: You could have a table view with the city and data in respective columns. Or a Google maps layer with pins for each city. Where each pin is a link to each event entity page.

If you are looking to enforce restrictions on people from attending both events, you can try RNG Conflict. However I don't think that is necessary in your case.