Legal Question

Dhacim is talking about the Dale City exit/entrance. Coming North just after the rest stop, I usually take the Dale City exit, stay on the 'access' road and rejoin the highway just south of the Prince William Parkway exit. I don't think that is illegal

No it is not illegal.

This from the VA Drivers Manual (pages 38 & 27 respectively):

Solid white lines designate turn lanes and
discourage lane changes near intersections
and at other locations where lane changes
might be dangerous. Solid white lines also
mark the right edge of pavement. Arrows
used with white lines indicate which turn
may be made from the lane. Stop lines,
crosswalks and parking spaces also are
marked by white lines.

Passing is prohibited:
on hills, curves, at intersections or
railroad crossings, except on roads
with two or more lanes of traffic
moving in the same direction;
off the pavement or shoulder of the
road;
when a school bus is stopped to
load or unload passengers on a
public road (unless a physical
barrier or unpaved median separates
traffic going in either direction)
or on a private road; and,
whenever a solid line marks the left
side of your lane.

I think it's safe to say that crossing any parallel solid line is illegal.

NoSb

SOV because you can, HOV because you care!