You can archive Initiatives from the Initiatives workflow just like you archive cards in the Cards Workflow.
First, move all completed Initiatives into the "Ready to Аrchive" column.
The system keeps your Initiatives there for a certain period of time (1/7/14/30 days).
The default setting is 7 days. After that time period expires, the cards will be automatically moved to the Permanent Archive.
Important: The Initiatives in the Permanent archive are zipped up and they can be restored anytime if needed. For more information, please check the dedicated article.
Note that Timeline initiatives cannot be archived and they will remain visible on your Timeline workflow.