How to cancel/delete a series of recurring events in one go?

Recurring events are often part of the same series and therefore have the same series ID. From the flow tab in an event you can see all the other events in the same series.

You can choose 'View All' under the flow tab of any event in the series, or you can perform a search to find all events with the same specific series ID, the results window will then show all the matching events and allow you to delete them or perform other available batch actions.