Mass deletingOver time, you may create pages you no longer need. If you have many pages to delete at once, you can do this in the Admin Panel > Admin Home > More Options > Clean-up tab.
If empty pages exist (ie. image galleries with no images) the Clean-up tab suggests these for deletion.
Clicking All Pages will also display pages with content you have uploaded. These pages will not be checked by default, like so:
Check the pages that you want to delete, and click Delete, and confirm the deletion when asked.