Milano Duomo Roof
The best part about this Cathedral is the access to the roof.  I have never seen access this good.  You can walk around all over, underneath flying buttresses and even to the apex of the roof for great views of Milan.  And, the other record-setting aspect of this church are the statues- 2245 of them in every conceivable location.  Check out the spires in this sequence of pictures to see how many literally cover each one of them.