Various links to sites related to bicycle advocacy and laws.
Do you know the definitions of highway and roadway? Do you know how these are used in the laws? When should you not ride as far to the right as practicable?
The Virginia Department of Transportation (VDOT) has a nice web site on bicycling in Virginia. Included on that web site are some definitions and laws that relate to bicycling on Virginia roads.
Definitions from the VDOT web site:
A vehicle is defined as every device used for the transportation of people or property on a highway.
A bicycle is defined as a device propelled solely by human power, having pedals, two or more wheels, and a seat height of more than 25 inches when adjusted to its maximum height. A bicycle is a vehicle when operated on the highway.
A highway is defined as the entire width between the boundary lines of every place open to public use for purposes of vehicular travel.
A roadway is defined as the portion of the highway improved, designed, or ordinarily used for vehicular travel, exclusive of the shoulder.
You can look up Virginia's Codes regarding bicycles in a searchable database. Of particular interest are where on the highway bicycles are suppose to ride, rules about riding two abreast, and use of hand signals.
Persons operating a bicycle on a roadway shall ride as close as practicable to the right curb or edge of the roadway. Except when .passing, turning left, avoiding obstacles, or the lane is too narrow for a motor vehicle to pass safely.
Persons riding bicycles on a highway shall not ride two or more abreast. Except for bicycle lanes.
Some success has occurred at the national level in wording the code to favor proper bicycle operation. Some of this wording has been reflected in the Uniform Vehicle Code, a non-binding document. Virginia's codes are not consistent with the Uniform Vehicle Code and, I believe, are overly restrictive on some reasonable bicycle usage. For example, see John Allen's article on bicycling two abreast.
National Organizations
State Organizations
Others