Help. How to cut the middle three boxes out?

[Autumn5CF1]

It's wierd that I can't find a way to do this. 

Tried using erasor, knife, scissors, clipping mask and minus front, nothing seems to work and keep getting errors I don't understand. Whats a simple way to to just cut these boxes out to reveal the background? Much appreciated help. Thanks 

[Ton Frederiks]

Did you try to use Live Paint?

Lock the background and use the Live Paint bucket to fill with none.

[Simmer1]

When using the Minus Front option you may need to Right Click and select Ungroup from the drop-down menu first. Then it should work.

[Jacob Bugge]

Autumn,

Whichever kind(s) of background you have, presuming the black part of the lighthouse/tower is vector artwork and at the very top, I believe you can (also) obtain it in this way:

1) Lock the outer background,

2) Copy the black part of the lighthouse on top of itself,

3) Select everything and Ctrl/Cmd+7 to create a Clipping Set.