Complex sentence: The Western Pacific Railroad Museum at Portola, formerly known as the Portola Railroad Museum (prior to January 1st., 2006) is a heritage railway located at Portola, California that preserves and operates historic railroad equipment.
Split into simpler sentences: The Western Pacific Railroad Museum at Portola was formerly known as the Portola Railroad Museum. The museum is a heritage railway located at Portola, California that preserves and operates historic railroad equipment.