If you press the following link you will see the google map I choose:

http://maps.google.es/maps?client=firefox-a&channel=s&hl=ca&q=sagrada+familia+barcelona+mapa&ie=UTF8&split=0&gl=es&ei=a8cSSt-4LYiZjAewx_SvBA&z=16&iwloc=A

These are the clues to guess what it is:

-It is a church.
-It was designed by Antoni Gaudí.
-You will find it in Barcelona.
-It is still in construction.
-It is the most famous monument of Catalunya.