Whenever any highway has been divided into two (2) roadways by leaving an intervening space or by a physical barrier or clearly indicated dividing section so constructed as to impede vehicular traffic, every vehicle shall be driven only upon the right-hand roadway and no vehicle shall be driven over, across, or within any dividing space, barrier or section, except through an opening in the physical barrier or dividing section or space or at a cross-over or intersection established by public authority.