Hi Paul,
Thanks for reaching out!
We do have a setting to clean up past recurring events. Go to Events > Settings > General, and you will see a setting (“Cleanup recurring events after”) where you can specify a number of months to keep past recurring events for, after which they will be deleted.
If you would like to delete old single (non-recurring) events, I would recommend taking a look at a plugin like this which will let you delete custom post types (events are “tribe_events” custom post types). If you go this route, make sure to back up your database prior to deleting the events!
I hope that helps, but please let me know if you have any more questions.
Thanks,
Jennifer