Perhaps the most famous gothic cathedral in the world, Notre Dame is located on the Isle de la Cite in the heart of Paris. It is particularly famous for its spectacular rose woods of stained glass and gargoyles. Tragically it was severely damaged by a fire in April 2019 during restoration work. Fortunately it seems that much of the art within the church including the rose windows, gargoyles, and flying buttresses, were all spared. The church is no reopened.
You can obtain free tickets 2 days ahead at midnight in an attempt to skip the line.