Closed Safari Tab via key combination to restore
The last Tab you've closed, you can call the Shortcut "cmd + Z" again. This only works, however, if you have in the meantime made otherwise - for example, an input in a text box.
Using the menu to the end of a Tab in Safari recall
Via the Safari menu bar, you come to the same result as the above-described keyboard shortcuts. Just click on "edit" and "Tab close to call". Also this Option only works if you have up and running in the between time no other action.
Safari Tabs to restore
Tip: Closed pages in Safari at any time to recover. For this purpose, in the menu go to the "history" button and then on the "Last closed window reopen".
The manual refers to the Version of Safari 6.0.3 on a MacBook Air under OS X 10.8.3.
