Complex sentence: During their honeymoon attending the Salzburg and Bayreuth festivals Christie and his wife came up with the idea of bringing professional opera to Glyndbourne, by creating a purpose built theatre with a 300 seat auditorium and a large orchestra pit.
Split into simpler sentences: During their honeymoon attending the Salzburg and Bayreuth festivals, Christie and his wife came up with the idea of bringing professional opera to Glyndbourne. They built a theatre with a 300 seat auditorium and a large orchestra pit.