After five years of speedy reconstruction work, Notre Dame will soon reopen. But the architect formerly in charge of Cologne Cathedral in neighboring Germany fears that things are moving too fast.

Paris' Notre-Dame Cathedral will reopen on Dec. 7, five and a half years after a devastating fire destroyed its roof and spire and caused major damage throughout.

The reconstruction of the monument included building a new roof and spire on top of the building. The restoration also revealed murals covered by centuries of grime.