Complex sentence: Highway 30 remained generally unchanged over the next 30 years, until January 1,1998, when the entire route was decommissioned and transferred to Northumberland and Peterborough counties.
Split into simpler sentences: Highway 30 remained generally unchanged over the next 30 years. On January 1,1998, the entire route was decommissioned and transferred to Northumberland and Peterborough counties.