cannot delete locations bar history

I can hide the history by changing what is displayed in the locations bar in the Privacy option, but I want to delete all the locations bar history and the locations bar changed back to display the new history. I have followed all the instructions given in the support pages. I have "cleared recent history" performed history clean-ups and used the drop down menu to delete individual webpages from the locations bar (they just come up again on a new search). Webpages are coming up in the suggested locations bar from months ago and are not used regularly.They are not bookmarks either. So I just want to delete all the old history and start my locations bar suggestions again.