Here are the steps to follow to archive a board:
Step 1. On your Dashboard page choose the board you want to archive by clicking on the 3 dots icon (ellipsis)
Step 2. Choose the option “Archive”
Final Step. Now click on the button “Yes, archive it!” to archive your board.
Note: Once you archive a board, only the board creator will be able to access the board and it will not be accessible by anyone with the URL anymore.
Here are the steps to follow to unarchive a board:
Step 1. First, you need to access the archived board page by clicking on “Show archived board” choose the option “Yes”.
Step 2. Go to the board you want to unarchive and click on “Unarchive”
Final Step. Now click on the button “Yes, unarchive it!” to unarchive your board.
Note: Once you unarchive a board, people with the URL will be able to access it again.