Complex sentence: The first is at the intersection of NH 123 and Cold River Road, approximately five miles from the beginning of NH 123 in New Hampshire, where a bridge was destroyed from high water in the Cold River.
Split into simpler sentences: The first is at the intersection of 123 and Cold River Road, approximately 5 miles from the beginning of 123 in New Hampshire. This was due to a bridge being destroyed from high water in the Cold River.