Do you open Safari on your iPhone 3G and find that address bar is missing?

Who knows  What could have done to cause this?  but here i will not discuss that what has caused this but i will be surely going to tell you that how you can bring your address bar back:, Follow The Steps Below,

Hold down the Shift + Apple key and then press the | key (above the Enter key).

or

Select View> Show Address Bar.

If that fails, try the following:

Choose View> Customize Address Bar … and drag the address bar back to the top of the screen Safari.