Is the intersection of national highway marked with solid line or dotted line?

Solid line. According to the inquiry of Grassroots Science Network, the intersection of national roads is marked with solid lines, and the solid white line is an insurmountable boundary, which divides the boundary of traffic flow and sometimes the center line of the road. The types of white solid lines are straight lines and circular arcs, and can also be divided into single lines and double lines. Considering safety and convenience, users should follow the standard and use solid white lines.