cathedral is that more than thirty kings were crowned here in the middle ages his crew needed an all clear and fogs and up stairs we have what's called charlemagne's throne which was probably built during his time here on the phone card. to toward us. in september of one nine hundred seventy eight the cathedral wasn't the only site here put on unesco's world heritage list the old imperial town surrounding the building is also listed. keeping the cathedral intact costs about one to two million euros per year back on the square the light show was about to begin and designer christoph helen makes the final technical checks and then it's all systems go. the kitty clothes extensive history throughout the ages is the subject of the lighting installation. and it seems