Starting a new event from one of your own, what is copied across, and what you have to fill in again.
Duplicate, beside Edit details at the top of Manage on your own event. It works on any event of yours, whatever its status — one that has already run, or one you canceled, as much as one still to come.
It opens the Create Event form already filled in from that event, with a note at the top saying which event it was copied from. Nothing is saved until you press Create draft, so you can change anything first or walk away.
What you save is a draft of its own, with its own address. It keeps no link to the event you copied: changing one never changes the other, and nothing on the new event says it was copied.
Publishing it works as it does for any new event — it needs a start date and a town, and a free event has its own publish fee. See publishing your event.
If the event you copy came from Webpoint, the copy does not. Its details are not locked, there is no Re-sync from Webpoint, and the sanction confirmation the original had does not come across — the copy is an event you typed in yourself. See importing an event from Webpoint.