Complex sentence: During filming in Linderhof Castle the temperature in the famed mirror hall got so high that one of the mirrors cracked as a result, it is to this day the only broken piece in the original decor of the hall.
Split into simpler sentences: During filming in Linderhof Castle the temperature in the famed mirror hall got so high that one of the mirrors cracked. As a result, it is to this day the only broken piece in the original decor of the hall.