How do you set up a campaign when you have one event invitation, for an event happening in three different cities ? Do you need a separate invite for each so you can capture registrations separately?

Is this a roadshow? As in they can choose the location they would like to attend? The way we set up our series is we create a main folder to house everything in. The create individual programs inside of that folder. Here is how it would look:

• 2014 - Webcast Series (or roadshow, or whatever works for you)
  • WC 2014-12-10 Session 1
    • build out all of your folders, assets, smart campaigns like you normally would
  • WC 2014-12-11 Session 2
    • For this you only need to build out any confirmation emails and reminders
    • For the smart campaigns you will need a registered step, a reminder step and a follow up ste

In our first session we would build everything there (we only send one email for our series since the dates are close together). We include tokens for our second program as well (yes, separate calendar file tokens as well)

For your flow steps this is where it can get a bit tricky, but it is doable. Here is how it would look:

• Smart List Session 1 (built in your first session)
  • Fills out Form > Form Name is (fill this out)
  • Webinar Registration > Webinar Registration Contains : Webcast 1 (this was a custom field we created in Field Management so we can track if they register for varying things - you will need to create this as well and include it on your form)
• Flow Step Session 1 (built in your first session)
  • Change Program Status > Select your program > New Status: Registered
  • Send Email > Confirmation for Reg 1
• For session 2 you would do the exact same thing except you would build it in that program. 

The reason we built ours out this way is we wanted to keep the members list specific to that program and not have everyone in one list. It gets hard to manage your flowsteps in just one program because of the members being all marked as registered. We found this to be the easiest and our emails and programs have run very successfully.

We test about a million times before deploying to make sure it is fool proof. Hopefully this helps!

I generally agree wit Nicole, so check out the walkthrough here
http://www.marketingrockstarguides.com/setup-recurring-webinars-in-marketo-1479/