There are guilds in France that have maintained the skills and knowledge of medieval stonemasonry and other old world building trades/crafts.
Someone posted data about them on the first big Notre Dame thread.
As Victor David Hansen has suggested, we no longer have the heart or transcendence to build such a structure.
Craftsmen back then did it out of love for their Lord and the Mother of God. People like that no longer exist in a godless Europe.