Um, that's what the history is. A list of sites you've visited before. It's your only option. Safari will auto-complete url's as you type them if it's in your history or bookmarks.
Perhaps a third party program or some network tool can see what you are doing. It won't matter if you clear the history or the cache.
[Edit]
Woman are getting wise to web surfing nowdays. Clearing the cache and history are clear signs of guilt. They will notice that and investigate. The best thing to do is go into Private Browsing mode and never clear your history. Keep your history clean and load it with some good stuff and you will be safe.